Account of a Filaria in a Horse's Eye. 283 
3. Filaria gracilis is found in apes and monkeys in great 
abundance. It grows toa length of ten or twelve inches, is 
about as thick as a fine thread, head obtuse, and tapering slightly 
at both extremities. 
A. Filaria attenuata. This species is found in the abdominal 
cavity of crows, also in the cornea of the eye of fishes. It is 
from one to six inches long, and obtuse at both extremities. 
5. Filaria obtusa inhabits the intestines of swallows. Its head 
is somewhat acute, tail obtuse, body comparatively thick and 
elastic, and has been found twelve inches in length. M. Ru- 
dolphi has traced out its intestinal canal and ovaries. : 
6. Filaria truncata. ‘This species is about five inches long, 
has a truncated head, a tail somewhat thick, obtuse, terminated 
by a very sharp point; inhabits the darva, or caterpillar of cer- 
tain species of moths. ( T%nea padelia.) 
7. Filaria ovale. This species formerly went under the name 
of Gordius piscium, (hair-worm of fishes,) because it is found in 
the liver of the carp. It is three or four inches in length; head 
oval ; tapering forwards ; tail round. 
8. Filaria capsularia.. From half an inch to an inch long, 
and resembles in thickness a middle-sized thread. ‘The borders 
of the mouth are recurved, resembling, according to De Blain- 
ville; the mouth of a pudding-bag ; tail obtuse, papilliform, and 
ending with a fine, sharp point. It occurs of both sexes, with a 
large intestinal canal and stomach. The female is more gross— 
often met with in the herring, in large quantities. It is very te- 
nacious of life; for Rudolphi states that he has known it live 
ight days in a dry place, and even to revive after having been 
long frozen im masses of ice. It is this species which Zeder and 
some other naturalists have formed into a genus, under the name 
of Capsularis. ; jhe 
9. Filaria papillosa. The Filaire equi of Gmelin, and the 
Gordius equinus of other writers. - This is the species which in- 
habits the eye of the horse. It is from one to seven inches in 
length, and about one-third of a line in diameter. It is usually 
of a yellowish white or ash color,—sometimes of a brownish hue. 
Head slightly obtuse ; mouth orbicular ; neck studded with pa- 
pille ; tail slender and curved. It occurs in different parts of the 
~ horse, chiefly in the muscles and intestinal eanal, though it has 
been detected in the brain, as well as the aqueous humor of the 
eye. 
