4.62 CLASS ECHINODERMATA. 
cially in infants, to whom it occasions a variety of affections, 
particularly when it ascends into the stomach. 
Other species have a small membrane on each side of the 
head. Such is, 
Ascaris vermicularis, L. Goetz. v. 1—6. Encyc. Meth. Vers. 
xxx. pl. x. 1. So common with infants, and in certain mala- 
dies of adults, in whom it produces an insupportable itching 
at the anus. It scarcely exceeds five lines in length, and is 
thicker in front. 
STRONGYLUS, Miill., 
Have the body round, and the anus enveloped in the male, 
by a sort of pouch, variously configured; and from which 
issus a small filament, that appears to serve the purpose of 
generation. ‘The female is destitute of these latter charac- 
ters, which might sometimes cause her to be taken for an 
ascaris. 
There are some of these strongyli which have ciliz, or den- 
ticulations to the mouth. Such is 
Strong. Equinus, Gm. Str. armatus, Rud. Mill. Zool. 
Dan. ii. xlii. Enc. meth. xxxvi. 7—15. Two inches long, 
with a hard spherical head, mouth furnished all round with 
small soft spines. The pouch of the male is divided into three 
leaflets. It is the most common of all the worms of the 
horse. It penetrates even into the arteries, where it occasions 
aneurisms. It is also found in the ass and the mule. 
Others have round the mouth, only tubercles or papille. 
Such is particularly, 
Strongylus gigas, Rud. Ascaris visceralis, et Asc. renalis, 
Gm. Rud., &c. The largest of the known intestinal worms ; 
it is two or three feet long and upwards, and of the thickness 
of one’s little finger. What is most singular is, that it is most 
frequently developed in one of the kidneys of divers animals; 
