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much beyond it; while it restricts the further southern migration of such birds as the white crowned sparrow (Zonotrichia leucophrys), the red cross bill (Curvirostra Americana), the pine finch (Chrysomitris pinus), the lesser red poll linnet (Aegiothus linaria), &c. Although so limited in area, the District of Columbia possesses, in woods, meadows, marshes, and streams, a character of surface so varied that every class of birds can find the peculiar situations they were designed to frequent. Its proximity to Chesapeake Bay, that great Winter resort for nearly all the ducks and other sea-fowl which retire to the far north to breed, and its situation along the Potomac River, one of its greatest tributaries, causes all the species to be found within its limits. But the incessant persecutions to which these birds are subjected have so materially decreased their numbers that they are every year becoming scarcer; and the great body of those that are left, intimidated by incessant harassing, have removed to the numerous bays and inlets along the sinuosities of the Carolinian and other southern shores. Its position along the banks of the Potomac affords the sandy and muddy flats which the sandpipers and the other smaller waders frequent; while the extensive marshes and swampy tracts, where the wild oats (Zizania aquatica) grow in profusion, furnish suitable food to the thousands of rail, blackbirds, and reed-birds, which at certain seasons frequent those localities in immense numbers. Along the beautiful little stream known
“ Rock Creek” are many shady, secluded hills, which, in the Spring and Autumn, abound with warblers, thrushes, and the smaller fly-catchers; while over its waters are to be heard at all times, during the Summer, the loud rattling of the kingfisher, the “peet-weet” of the spotted land
piper, and the green heron is seen to fly slowly along beneath the overhanging branches. The thick cedars which border this creek are favorite resorts of the beautiful cardinal grosbeak or Virginia red-bird (Cardinalis Virginianus), so well known and justly celebrated both for the beauty of his plumage, and the richness and melody of his pleasing song. There are also extensive meadows to be found in every direction, which furnish a suitable abode for the lark (Sturnella magna), the blackthroated bunting (Euspiza Americana), and the various species of sparrows which are never found but in such situations. Though the number of birds resident throughout the year, and which breed here, is considerable, they are few in comparison with the numbers that pass through the District during their Spring and Autumn migrations, and those which are merely visitors during the Summer and Winter months—the former from a more southern climate, the latter from the northern regions. As an example of the number of birds which pass through on their way to the north to breed, we may cite the wood warblers, or Dendroicas. Of the twelve species which are found more or less abundantly in Spring and Autumn, but three, the common Summer yellow bird (D. æstiva), the pine-creeping (D. pinus), and the prairie warbler (D. discolor), breed here at all, and the last of these is rare. Again, of the six species of thrushes (Genus Turdus) which are abundant during their migrations, but two, the robin (T. migratorius), and the wood thrush (T. mustelinus), remain during the Summer. The same might be said with reference to the smaller fly-catchers, the sandpipers, &c. Those birds which visit us in the Summer are for the most part the young of species which breed further south,
and are generally observed in the months of July and August. Such is the case with regard to the small blue heron (Florida coerulea), the white ibis (Ibis alba), the great white egret (Herodias egretta), and some others. Among our rarer Winter visitants are the white crowned sparrow (Zonotrichia leucophrys), the great northern shrike or butcher-bird (Collyrio borealis), and in severe Winters the snowy owl (Nyctea nivea), and probably the snow bunting (Plectrophanes nivalis). The occurrence of a few other species in this vicinity must be looked upon as purely accidental and dependent on no fixed habit of the bird. Thus, during a violent easterly storm a few years ago, the Potomac was covered with multitudes of Mother Cary's chickens (Thalassidroma Leachii), which had been forced out of their usual course by the gale. The single instance of the occurrence of the ground dove (Chamaepelia passerina) in this vicinity must be regarded as equally accidental. Two hundred and thirty-six species of birds have been collected in the District.
Herpetology.-Considering the small extent of the District of Columbia, there are several features of much interest in regard to its reptiles. The number of species is quite large, amounting, as will be seen, to over fifty, some of them being very rare. As in other departments of zoology, there is a mixture of the northern and southern faunas, although the prevailing character of the herpetology is, perhaps, southern rather than northern.
Of the turtles, some of the species extend their range over wide areas of the country, while others are much more restricted. The well-known diamond-backed or saltwater terrapin (Emys terrapin) is common in the lower
brackish waters of the Potomac River, and probably comes but rarely of its own accord into the District. As a delicacy this species takes rank with the canvas-back duck. Another terrapin, the Emys rubriventris, or redbellied terrapin, very common in the Washington market, attains a large size, and is much esteemed as an article of food. The snapping turtle (Chelonura serpentina) is also frequently found on the stalls of the dealers. The total number of species of turtles found within the District is about nine. One of them, the Emys picta, finds here nearly its southern limit, while the E. terrapin and rubriventris, both tide-water species, are not met with much further to the eastward.
Of the true lizards, with scales, three species only have yet been found in the District, though one or two more may yet be detected. One of them, the Sceloporus undulatus, a rough, brown species, with blue neck, may frequently be seen running along the fences by the roadside. The six-lined lizard (Chemidophorus sexlineatus) seldom occurs further north. The blue-tailed lizard, with five white lines (Plestiodon), is often found in wood-piles.
The list of serpents found about Washington is quite extensive, embracing at least twenty-one species. The most important of these is the deadly copperhead snake (Ancistrodon contortrix), not uncommon about the Little Falls. The rattlesnake is not now known to inhabit the District, though doubtless once a resident. Other serpents are the well-known black snake, various striped or garter snakes, water snakes, etc. Blowing vipers or hog-nosed snakes, erroneously believed to be venomous, are sometimes met with. The slender green snake (Leptophis æstivus), characteristic of a southern fauna, as also Lam
propeltis getula, the chain-snake, are quite abundant. The rare L. clerica has several times been met with.
Of the group of frogs and toads nine species are known, of all sizes, from the huge bull-frog, to the cricket-frog not larger than a blue-bottle fly, and very abundant in the slashes north of the city, where its singular note, resembling the sound of two pebbles struck rapidly together, may constantly be heard in the Summer season. The most curious species of all, however, is the spade-footed toad (Scaphiopus Holbrookii), which though quite abundant is very rarely seen, owing to its remaining buried up in sand or loose earth almost all the time, and coming out only during wet and stormy nights. The spade-shaped attachment to the hind feet is used to scoop out the earth, into which it speedily sinks and is covered up.
Of the remaining group of reptiles—the salamanders, or water lizards, with smooth, naked, slimy skins, and living under damp logs, or stones, or in the water—there are about ten species, making fifty-two species, in all, of reptiles actually collected in the District.
It may be well to mention here, by way of correcting a popular impression in the vicinity of Washington, that, with the exception of the copperhead (unless the rattlesnake still exists), there are no poisonous reptiles whatever in the District. However threatening in their actions the blowing vipers or adders, the black snakes, the green snakes, or the water snakes may be, all, with the exceptions mentioned, are entirely destitute of venomous properties, although the scratch from their teeth might produce a festering sore, similar to that sometimes caused by a pin or needle. The lizards of all kinds, whether of the kind popularly known as scorpions by the country people, or