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ous localization of germ-plasm in plants. this germ-plasm is inextinguishably associWeismann himself admits that the germ- ated with every cell of the plant body, why plasm must be distributed in ‘minute frac- does it not receive and transmit all incident tion’ in all somatic nuclei’ of the begonia impressions upon the plant? Why should leaf, because that leaf is capable of giving acquired characters impress themselves rise to new plants, by means of cuttings, upon the soma-plasm and not upon the and all the plants may produce good germ-plasm when this latter element is flowers, which, if they are sexual at all, are contained in the very nuclei, as Weismann so only by virtue of containing some of this admits, of somatic cells? If the theory of elusive germ-plasm. There is no other way the continuity of the germ-plasm is true for for these plants to get their germ-plasm, ex- plants, then acquired characters must be cept from the somatic leaf from which they transmitted! The only escape from this came. It would seem that this admission position is an arbitrary assumption that one undermines the whole theory of the local- plasm is impressionable and that the other ization of the germ-plasm in plants, for one is not ; and, now, that we can no longer relexception in the hypothesis must argue egate the germ-plasm to imaginary deepthat there are others. But not so ! There seated germ-cells, such an assumption is too are no insurmountable difficulties before bold, I think, to be suggested. the Weismannians. It is the begonia which The entire Weismannian hypothesis is is the exception, for it is abnormal for plants built upon the assumption that all permato propagate by any such means !
nent or progressive variation is the result swer which has been made to this state- of sexual union; but I have shown that ment is that very many plants are propa- there is much progressive variation in the gated asexually by horticulturists, and that vegetable kingdom which is purely asexual, all plants can probably be so propagated if and, for all we know, this type of modificathere were any occasion for the effort. tion may proceed indefinitely. There is no This answer is true ; but the philosophical doubt of the facts; and the only answer to answer is that every phyton is an autonomy, them which I can conceive the Weismannian and that the mere accident of its growing to make is that these progressive variations on the plant, in the soil, or in a bottle of arise because of the latent influence of anwater, is wholly aside from the point, for cestral sexual unions. In reply to this I wherever it grows it lives at first a sexless should ask for proofs. Hosts of fungi have life, it has an individuality, competes with
I am not convinced but that there its fellows, varies to suit its needs, and is may be strains or types of some species of capable, finally, of developing sex.
filamentous algæ and other plants in which Another fundamental tenet of Weis- there has never been sexual union, even mannism is the continuity of the germ- from the beginning. And I should bring, plasm, the passing down from generation to in rebuttal, also, the result of direct obsergeneration of a part or direct offspring of vation and experiment to show that given the original germ-plasm. Now, if there is hereditable asexual variations are often the any continuity in plants, this ancestral direct result of climate, soil or other imgerm-plasm must be inextricably diffused in pinging conditions. As a matter of fact, the soma-plasm, as I have said, for every we know that acquired characters may be part or phyton of these plants, even to the hereditary in plants; if the facts do not roots and parts of the leaves, is able to pro- agree with the hypothesis, so much the duce sexual parts or germ-plasm. And if worse for the hypothesis. Unfortunately,
the hypothesis is too apt to be capable of ticle of the plant body, even to its very peendless contractions and modifications to riphery, and it must directly receive external meet individual cases. I sometimes think impressions; and this concept of Weismann that we are substituting for the philosophy —the continuity of the germ-plasm-beof observation a philosophy of definitions. comes one of the readiest means of explain
I have, therefore, attempted to show : ing the transmission of acquired characters.
1. That the plant is not a simple autono- All these conclusions prove the unwisdom my in the sense in which the animal is. of endeavoring to account for the evolution
2. That its parts are virtually independent of all the forms of life upon any single in respect to (a) propagation (equally either hypothesis ; and they illustrate with great when detached or still persisting upon the emphasis the complexity of even the fundaparent plant), (b) struggle for existence mental forces in the progression of organic amongst themselves, (c) variation, (d) nature.
L. H. BAILEY. transmission of their characters, either by CORNELL UNIVERSITY. means of seeds or buds. 3. That there is no essential difference
CURRENT NOTES ON PHYSIOGRAPHY (III.). between bud-varieties and seed-varieties, WOODWARD'S SMITHSONIAN GEOGRAPHICAL apart from the mere fact of their unlike derivation; and the causes of variation in "The average geographer,' to whose needs the one case are the same as those in the Professor Woodward has attempted to suit other.
the recent volume of Geographical Tables 4. That all these parts are at first sexless, issued by the Smithsonian Institution, but finally may or may not develop sex. should certainly feel highly complimented
5. That much of the evolution of the by this tribute to his quality. The volume vegetable kingdom is accomplished by contains, among many other matters, tables wholly sexless means.
of coördinates for the projection of polyThere is, then, a fundamental unlikeness conic maps, lengths of a degree on parallels in the ultimate evolution of animals and and meridians at different latitudes, areas plants. A plant, as we ordinarily know it, of latitude-and-longitude, quadrilaterals of is a colony of potential individuals, each one different dimensions and at different latiof which, save the very first, is derived from tudes, adopted dimensions of the earth's an asexual parent, yet each one may, and spheroid, value of gravity at the earth's surusually does, develop sex. Each individual face, and salient facts of physical geodesy. is capable also of receiving a distinct or pe- The latter heading includes the area of the culiar influence of the environment and earth, of oceans and continents, and the struggle for existence, and is capable, there
average heights of continents and depths of fore, of independent permanent modifica- oceans, taken from Helmert's Geodäsie. For tion. It is not possible, therefore, that there areas the continents are given 51,886,000, is any localization or continuity of a germ- and the oceans 145,054,000 square miles. plasm in the sense in which these concep- The mean depth of the oceans is placed at tions are applied to animals; nor is it pos- 3,440 meters. The mean heights of the consible for the plant as a whole to make a tinents are given as follows: The earlier resimple functional adaptation to environ- sults of Humboldt's, still often quoted, and ment. If there is a continuity of germ- the later ones of Penck (Morphologie der plasm in plants this element must of neces- Erdoberfläche, 1894) being added for comsity be intimately associated with every par- parison.
Humboldt. Helmert. Penck. whatever shape, they form only a comparaEurope,
205 300 330. m. tively thin growth upon the underlying Asia,
351 500 1010 base” (p. 177). The text, with its figures, Africa,
500 660 supplemented by maps and plates, gives an Australia,
250 310 excellent idea of the geographical features North, 228
of the region and of their evolution. America,
650 South, 346
650 All Continents, 308 440 735
SPENCER'S RECONSTRUCTION OF THE
LEAN CONTINENT. The increase in the values of the latter measures is probably an approach to the
PROF. MARCEL BERTRAND, of the École truth, for early explorations frequently gave
des Mines and the Geological Survey of too much emphasis to narrow mountain
France, has published an account of certain ranges, and too little to broad plateaus.
faint deformations of northwestern France,
in which he interprets the inequalities in A. AGASSIZ ON THE BAHAMAS.
the floor of the English channel as the reA RECONNOISSANCE of the Bahamas and of sult of faint anticlinal and synclinal movethe elevated reefs of Cuba, made by A. ments (Bull. Soc. Géol. France, xx., 1892, Agassiz in the winter of 1893, affords 118); thus implying that neither erosion material for a Bulletin of 200 pages with 47 nor deposition has been of significant measplates and many figures in the text, lately ure in shaping the channel floor. Prof. J. issued by the Museum of Comparative Zo- W. Spencer takes almost the other extreme, ology at Harvard College. The author is and interprets certain inequalities of the emphatic in rejecting the sufficiency of the ocean floor of the Antillean region, even to Darwin-Dana theory of submergence in ex- depths of twelve or fifteen thousand feet, as plaining the features of great limestone the results of river erosion during a not rebanks. The Bahamas consist of low hills mote time when the entire region is supofæolian limestone, " formed during a period posed to have had a much greater altitude of rest, during which the great beach of the than at present (Bull. Geol. Soc. Amer., vi., then existing reef constantly supplied fresh 1895, 103–140); thus implying that no material to be changed by the surf and the other processes than river erosion can acwinds into sand for the heaping up of sand count for the inequalities that he has traced. dunes. They could not be formed in a dis- It must be concluded from these contrasted trict of subsidence unless the subsidence was arguments that the forms of the sea floor slower than the rate of growth of the corals, are not yet so well understood as those of which is not the case in the Bahamas, as the the land ; because the facts are much less reefs of to-day, even when they come to the accurately known under than over sea level, surface, are not the sources from which the because only form and not structure can be material for the great dunes of the Bahama determined by soundings, and because the Islands is derived” (p. 184, 185). At pres- forms of the sea floor have received relaent the dunes are disappearing before the tively little study. Where two specialists action of the sea. The conclusion of the re- reach conclusions so unlike, it is difficult connoissance seems to be that the great for others to choose between them; and for limestone banks are chiefly formed as the present there will probably be some
marine limestones,' accumulating at great hesitation in adopting the teachings of the depths by accretion;' and that in the West one or the other. With much interest Indies “ wherever coral reefs occur, and of aroused in the facts brought forward, and with all willingness to look on the conti- otherwise moved with respect to its basenents as unstable, it is difficult to believe level. Its rocks are of diverse resistance, that they have suffered changes so great as and hence there may have been repeated Spencer announces, not only in the uplift of opportunities for diversion and rearrangethe Antillean region, but in the deep de- ment of river courses during the long life pression of the axis of Central America, and of the region as a land area. While admitin the denudation of the (inferred) great ting that several geological basins of great banks or continental shelf along the Wind- antiquity are now drained by a single river, ward Islands. The strongest proof will be it does not necessarily follow that this river demanded before vertical movements of is an immediate descendant of the rivers two miles and a half can be accepted; and which at one time or another drained the we fear that most readers will take refuge separate basins. The actual St. John river in a verdict of not proved.'
may once have been larger than now; its
neighbors may have gained drainage area HISTORY OF THE ST. JOHN RIVER, NEW from it instead of losing drainage area to it; BRUNSWICK.
but these possibilities are not considered. An article on the ‘Outlets of the St. John river,' by G. F. Matthew (Bull. Nat. Hist.
THE ORIGIN OF THE MISSISSIPPI. Soc., New Brunswick, xii., 1894, 43–62), THE reference to the Mississippi in the concludes that this river has been built up previous paragraph brings up an oft-encounby contributions from three other systems, tered implication of simple history in the whose lower parts are now to be seen in the development of this great river, against Restigouche, Miramichi and Petitcodiac. which there is much evidence. A similar The evidence of this conclusion is derived implication is found in a recent State Surfrom the geological structure of the coun- vey Report, where it is stated that, as a retry, beginning as far back as the Huronian sult of continental evolution at the close of time; the three rivers whose upper basins the Carboniferous period, the drainage of now belong to the St. John having been de- the Ohio region was turned southward fined as basins of deposition in more or less “into the great Mississippian bay, which remote geological periods. Thus the St. then washed the shores of the new-born John river has attained its present magni- continent as far north as the mouth of the tude by the breaking of mountain or hill Ohio river”' (Geol. Coastal plain of Alabama, barriers which once separated its three river 1894, 11). It is found again in the Story systems, and is not a simple valley of con- of the Mississippi Missouri,' where the tinuous growth like the Mississippi (p. Mississippi at the close of the Appalachian 55). The difficulty of accepting Dr. Mat- revolution is described as heading somethews' conclusion as the only solution of where in the Minnesota-Wisconsin region, the history of the St. John does not lie in and flowing southward to its mouth someany objection to the geological history of where near the present city of St. Louis, the region and its several basins of deposi- whence a deep gulf extended southward to tion, as far as stated, but in the omission of the present Gulf of Mexico (Amer. Geol. sufficient consideration of what has hap- iii., 1889, 368). While the southwardpened in the region since it became a land flowing streams of the Wisconsin-Minnesota area. It has long been subject to subaërial highlands are probably of ancient origin, erosion. During this time it has in all the southward course of the Mississippi beprobability been variously warped and tween Tennessee and Arkansas seems to
have been initiated not at the close of the appropriate for the official publication of Appalachian revolution, but long afterwards physiographical discussions. It therefore in Cretaceous time. The Appalachian revo- occasions regret to find so little account of lution formed the mountains of Arkansas, the origin and meaning of the Chunnenugga as well as those of the Alleghany belt. The ridge and the Black prairies of Alabama in similarity of structure is so great that a the elaborate report on the Geology of the trans-Mississippian extension of Appala- Coastal Plain lately published by the Survey chian growth may be reasonably assumed, of that State. “The Chunnenugga ridge is as has been pointed out by Winslow (Bull. made in great part by alterations of hard G. S. A., ii., 1891, 231). The existence of limestone ledges and bands of indurated a bay, from the Gulf of Mexico northward sands of the Ripley.
It overlooks towards St. Louis, is very improbable as a the low trough of the black prairies of the result of the Appalachian revolution ; an Rotten limestone towards the north with east and west constructional mountain belt somewhat precipitous slopes in that direcis a more likely product; and not until this tion, while its descent towards the south is mountain belt was well denuded to a pene- much more gentle” (p. 356). It is maniplain did a later deformation depress it fest that the ridge with its inland-facing transversely, admitting the Cretaceous escarpment and the denuded inner lowland waters northward across it, and thus first are typical features of a certain stage in the forming the Mississippi embayment. Prob- denudation of a coastal plain that consists ably in part at the same time, and to a of more and less resistant strata ; the draingreater extent in later time, the denuded age of the lowland being chiefly gathered peneplains to the east and west were raised by subsequent streams that have been detowards their present upland altitude, and veloped along the strike of the beds, and disas a result of this elevation the existing charged by consequent streams which mainvalleys and lowlands were opened in them tain transverse valleys through the enclosduring some part of Tertiary time. With ing ridge or upland. This general relation these later elevations we may associate the of form and drainage is so often repeated on uplift of the filled embayment and the coastal plains that its occurrence in Alabama southward growth of the Mississippi as a deserves mention as a local example of a river. This view of the origin of the Mis- general physiographic feature; just as the sissippi embayment and of the date of the Cretaceous strata on which it is developed southward discharge of Mississippi drainage deserve mention as local examples of a widewas first published by L. G. Westgate spread geological formation. (Amer. Geol. xi., 1893, 251), as a result of
W. M. Davis. conference with L. S. Griswold, who had HARVARD UNIVERSITY. then recently completed his investigation of the novaculite region of Arkansas.
THE NEW YORK MEETING OF THE ASSOCI
ATION OF AMERICAN ANATOMISTS. THE CHUNNENUGGA RIDGE AND THE BLACK
The Seventh Annual Session of the AmerPRAIRIES OF ALABAMA.
ican Anatomists was held in the Medical It is, perhaps, too much to expect that the Department of Columbia College, 437 West origin of the physiographic features of a 59th Street, New York City, December 28 region should always receive due attention and 29, 1894. in a geological report along with the origin The Association was called to order Friof its strata ; yet there is no other place so day, December 28th, by the President, Dr.