PARENCHYMATA. 413 
a proboscis, armed with little hooks bent posteriorly, and susceptible of 
being retracted or protruded by the action of particular muscles. At 
its extremity we sometimes observe a papilla or pore which may be an 
organ of absorption, but it is certain that if the animal be plunged 
into water it becomes universally distended, and absorbs that liquid 
through the whole surface, on which it is thought we can discover a 
network of absorbent vessels. No other parts that can be compared 
to intestines are visible internally, than two slightly elongated ceca 
attached to the base of the tubiform prominence; a vessel extends 
throughout its length on each side. A thread that runs along the 
inferior face of the animal is considered by M. de Blainville as its 
nervous system; but neither Rudolphi nor Cloquet coincide with him. 
Certain species have a distinct oviduct; in others the ova are disse- 
minated throughout the cellulosity or parenchyma of the body. The 
males are provided with a httle bladder at the end of the tail, and 
very distinct internal vesicule seminales. We may believe that they 
fecundate the ova after they are extruded. 
These worms cling tothe intestines by means of their proboscis, 
and frequently penetrate through them, so that individuals are some- 
times found in the thickness of their tunics, and even in the abdomen, 
adhering to their external parietes. 
E. gigas, Gm.; Geetz., X, 1—6; Encyc. XXXVI, 2—7. The 
largest species known; it inhabits the intestines of the Hog and 
Wild Boar, where the ‘females attain a length of fifteen inches *. 
Certain species, in addition to the prickles on their proboscis, are 
armed with them in some other part of the body. 
Heruca, Gm, 
Only differing from Echinorhynchus in the prominence, which is re- 
duced to a single crown of spines, terminated by double hooks. 
H. murts, Gm.; Echinorhynchus heruca, Rud.; Geetz., IX, 
B., 12; Encyc., Vers, XXXVI, 174. Itinhabits the liver of 
Rats. 
FAMILY II. 
TREMADOTEA, Rud. 
Our second family comprises those which are furnished underneath 
the body, or at its extremity, with organs resembling cupping-glasses, 
by which they adhere to the viscera. 
They may all be united in one genus, or the 
Fasciowa, Lin., 
Which may be subdivided in the following manner, according to the 
number and position of their organs of adhesion. 
* For the other species see Rud., Hist. I], 251, and Syn., p. 63. 
+ Id., Ib., 292, et seq. 
