To be taken at 9 a. m., and followed by one ounce of castor oil.

August 8th. Temperature normal and patient feeling well. He insists upon going out.

March 22, 1903. I saw the patient today and he says that his health is fine. He has not been sick since leaving the hospital.

HISTORICAL.

The parasite was discovered by Bilharz in 1851 in the intestine of a young man who died of meningitis. The worm was found in great numbers. A description was given by Von Siebold and Bilharz a little later. Leuckhart afterward gave a complete description from specimens given him by Bilharz. Four specimens of this tænia are found in the collection of worms in the College of the Faculty of Medicine in Paris. They had been given to Dr. Davaine by Burguieres.

Hellich, in 1885, obtained some of these worms in a child seven years old. This was the daughter of a barber. She was given male fern and passed a tænia solium, a few oxyuris vermiculares, and about fifty tænia nana.

Other doses of this drug were given and in five successive times she passed 250 of the worms. Leuckhart received some of these specimens and identified them as tænia nana. There are specimens to be found in the museum of Orfila said to have been given by Professor Dokitch in September, 1885, secured while traveling in Servia.

In 1873, Spooner found a small worm in the United States, which he thought to be tænia nana. The specimens were given to the College of Physicians of Philadelphia. Leuckhart is disposed to think the specimen was tænia flavopunctata. If this was tænia nana then it was the first case occurring in North America.

Grassi, in 1887, called attention to the fact that tænia nana was

a very common parasite in Sicily. He said it had several times been found in Lombardy.

It was observed in a young Nubian in Cairo in 1885 by W. Innes. Ransom reports finding a case in England in 1888.

Geographical Distribution.—This tænia has been found in many parts of the world. Bilharz discovered the parasite in Cairo. Dr. Haley found the worm in a seven year old child in Belgrade.

Specimens were obtained from Servia in 1885. Spooner thinks he found the tænia in the United States at Philadelphia. Grassi says this is a very common parasite in Sicily. He secured specimens of the worm from the two Sicilians. Ransom observed tænia nana in England. It is known to exist in Lombardy (Grassi, Comini, etc.). Piedmont (Peroncito), Tuscany (Sonsino), and Sicily (Grassi and Calandruccio). Grassi found it in Marseilles. Zograph found it in Russia; Mertens in Germany. Lutz found it in two little girls in Brazil. Wernicke and Blanchard found the worm in the Argentine Republic.

My case evidently contracted the parasite here in the vicinity of Galveston. There were two men working on the section with this man who had diarrhea of the same character, but I was unable to secure feces for examination. I feel convinced, since finding tænia nana in this man, that the other two were also infected.

Dr. Stiles writes me that he has recently found four cases in Georgia, and one of his assistants has found another case in an asylum in Washington.

The parasite is evidently much more widely distributed than we have heretofore thought.

GENERIC AND SPECIFIC DIAGNOSIS.

Genus Hymenolepis Weinland, 1858.

Generic Diagnosis.—Dipylidiinæ: Body small, filiform; head small, rostellum retractile, well developed and armed with a crown of twenty-four to thirty small hooklets; or rudimentary and unarmed; suckers usually unarmed; neck long; lateral border of strobila has serrate appearance much like the toothed edge of a saw

blade. Genital pore single, unilateral, on left margin. Testicles usually three to each segment, two on right, one on left side. Gravid segments transformed into a sac full of clear, round or oblong eggs, which are surrounded by three shells; internal shell occasionally with a small knoblike structure at each pole.

Larva a cryptocyst, or a staphylocyst.

Type Species.-Tania flavopunctata (Hymenolepis diminuta). Synonyms.—Hymenolepis Weinland, 1858; Diplacanthus Weinland, 1858 (not Agassiz, 18, fish); Lepidotrias Weinland, 1858; Diplocanthus Cohn, 1899 (misprint).

For list of species and bibliography see Blanchard, 1891, Hist. Zool. et Med. des T'eniad'es du genre Hymenolepis. Paris, 112 pp., 22 figs.

THE DWARF TAPEWORM.

Hymenolepis nana (Siebold, 1852) Blanchard, 1891.

Specific Diagnosis.-Hymenolepis: Strobila attains 10 to 40 mm. in length and 0.5 to 0.9 mm. in breadth; composed of about 150 to 200 segments. Head subspherical, 0.25 to 0.33 mm. in diameter; rostellum thick retractile, 100 long, 80 to 90 broad; hooks 20 to 30 in number, 14 to 18 long, and arranged in a single row; suckers lobular, 90 to 105 (according to some authors to 200) in diameter. Unsegmented neck quite long, not distinctly defined from head and about half as broad. Anterior proglottids very short, scarcely distinct; the following become gradually longer and broader, always remaining broader than long, attaining 0.14 to 0.30 mm. in length by 0.41 to 0.92 mm. in breadth. Vitellogene gland globular. Only about 100 eggs found in gravid segments; eggs globular to oval; outer envelope 30 to 60; inner envelope 16 to 28, presenting at each pole a more or less conspicuous mammillate projection provided with filamentous appendages; onchosphere 16 to 22 by 18 to 20 in diameter; hooks of onchosphere 10 to 14 long.

Synonyms.-Tania nana von Siebold, 1852 (not P. J. van Benden, 1861); Tania Egyptiaca Bilharz, 1852; Diplacanthus nanus

Weinland, 1858; Tania (Hymenolepis) nana Leuckart, 1863; Tania murina Dujardin (not Gmelin, 1789).

Description of Specimens.-Fig. 3 shows four segments in which it is seen that the genital opening is on the same side as the segments. These segments are almost far enough toward the tail end to contain mature ova, as one is seen at a.

Owing to the specimens being in a poor state of preservation no minute observations could be made, but one can make out the remnants of the male genital, which are seen in drawing. The immature ova have filled the uterus and make it conform to the shape of the segments.

The Ova.-The mature segments, which contain from 20 to 30 ova, were carefully studied.

When the ova are first encountered Fig. 4 gives a good idea of their appearance.

The hooklets of the embryos being seen without any difficulty at all. The interval between the outer and inner shells is seen upon very close observation to be made up of a substance which is quite clear, but running through it and apparently coming from what may be termed the poles, are a number of filaments. These are made out with great difficulty. Fig. 5 shows this quite well.

Lying within the inner shell is the embryo, which has six hooklets in most cases, but quite a number of ova were seen having only five, due probably to their being obscured by the others.

The average for a number of measurements was outer shell 40 u by 31.9 u, the inner shell 29.2 u by 26.6 u.

The hooklets which are shown in the ova measured from 10-13 u in length. Fig. 7 shows a hooklet enlarged.

Pathological Significance.-It is not known definitely how the infection is gotten, but from the great number found in the intestines it has been suggested that the ova are taken into the stomach with water or vegetables. It is not my aim to discuss this phase of the subject here, but it is quite desirable that some one discover the means of infection. This parasite has been found in large numbers in the small intestine and they have been known to pass

through the ileo-cœcal valve.

inhabit a single intestine.

Thousands of these worms may

The symptoms may be divided into two main groups: (1) Intestinal; (2) nervous.

From the irritation of the mucous membrane of the intestine there is apt to be loss of appetite, diarrhea, alternating with constipation, colicky pains in the abdomen and stomach, and great

nausea.

The nervous symptoms are headache, disturbance of vision, dizziness, melancholia and in many cases attack of epilepsy.

Where only a few parasites are present there may be no symptoms at all, but if the worms are numerous the symptoms are apt to be of a severe character. Anæmia follows later with its train of symptoms.

One is somewhat at a loss to account for such severe symptoms where so few worms are present, but as they rapidly disappear upon ridding the patient of the worms the parasite must be responsible for them.

It must be the combined irritation to the intestine and the liberation of toxins. The predominant symptoms in my case were obstinate diarrhea, cramps in the abdomen and limbs, headache and great weakness. One dose of the anthelmintic completely relieved him.

Diagnosis. The diagnosis is readily made by examination of the stools microscopically. The ova are easily recognized.

Treatment.-Male fern is the best drug to use for their expulsion. One drachm of the oleo-resin of male fern taken after a fast and followed by an active purge is usually all that is needed. Thymol and santonin are said to be of no value.

I am very much indebted to Dr. Charles W. Stiles, Chief of Division of Zoology, for the generic and specific diagnosis and for his aid in the study of the ova and the segments. And to Dr. A. J. Smith for his assistance in the preparation of drawings and his assistance in many ways. Also to Mr. B. N. Ransom for his excel

lent drawing of the egg.