INFESTING THE MUSCLES OF THE HUMAN BODY. 317 
but continuing of uniform diameter from that point to the opposite extremity. It is 
only at the larger extremity that I have been able to distinguish an indication of an 
orifice ; but this indication has been so constant in a number of individuals, examined 
under every variety of circumstance, that I have no hesitation in ascribing a large trans- 
verse linear mouth to the great extremity, which I therefore consider as the head. 
A recently extracted worm, seen by a Wollaston’s doublet before any evaporation of 
the surrounding moisture has affected its integument, presents a smooth transparent 
exterior skin inclosing a fine granular and flaky substance or parenchyma ; and after 
carefully testing various appearances of more complex organization, that have on dif. 
ferent examinations presented themselves, I now believe that the only structure that 
can safely be ascribed to this minute Entozoon is the simple one above described, It is 
not of a rigid texture, but is extremely fragile, and exhibits when uncoiled a tendency 
to return in some degree to its former state. 
It is curious to watch the variety of deceptive appearances that successively present 
themselves as the worm dries by evaporation. One of the most constant is a succes~ 
sion of minute transverse ruge, especially at the concave sides of the coils, which give 
a finely annulated character to the worm, but of which no trace can be perceived in the 
plump recent specimens when observed by a good doublet. Another appearance, which 
is more difficult to be accounted for, results from one and sometimes two longitudinal 
lines extending over a greater or less proportion of the body ; but these are not to be 
perceived in worms examined under circumstances least liable to cause deception. As 
evaporation proceeds, the wrinkling of the integument produces an appearance of the body 
being occupied by minute tortuous tubes, and a beautiful microscopical effect is thus ob- 
tained ; but the fallacy of this appearance and its true cause are easily detected. 
The test of coloured food could not be applied to elucidate the form of the digestive 
organs in the present instance: there was not any indication of the polygastric struc- 
ture, which, indeed, was hardly to be expected, since it does not exist in those Ento- 
zooid Infusoria which most nearly resemble the parasitic species in question, There 
was no appearance of the parietes of an alimentary canal floating in a visceral cavity 
and distinct from the integument of the body, asin the higher organized Nematoid 
Entozoa ; nor could a trace of an orifice, or anus, be observed at the smaller extremity. 
I have been equally unable to detect a projecting spiculum, or hook, at either extremity, 
or any appearance of the worm having been torn from an attached cyst. The natural 
transparency of this species is such as not to admit of a doubt as to its wanting the 
ovarian and seminal tubes and other characteristics of the complicated structure of 
Filaria, Ascaris, and the Nematoid Entozoa generally. 
Three species of small Nematoid Worms are described by Zeder as inclosed in cysts 
or capsules, and hence were termed by him Capsularia. Rudolphi, however, whose au- 
thority on this subject cannot be lightly disregarded, does not sanction or admit this 
VOL, I, 2u 
