98 VETERINARY PARASITOLOGY 
The Coccitdium cuniculi of the rabbit is identical, and 
these rodents act as harbourers and carriers of the 
parasite. 
3. Tenia Cysts in the Liver.—Tenia may be present 
in the liver, as embryos passing through on the way 
to the peritoneum or encysted therein. Of the former 
Cysticercus pisiformis may be taken as an example. 
These cysts invade the liver of rabbits in the form of 
miliary nodules, greyish in colour, with thick envelopes, 
guite distinct from the thin walls of the Coccidium cysts. 
They remain in the liver from three to four weeks 
before escaping into the peritoneal cavity. 
Echinococcus Veterinorum.—This is the cystic stage 
of Tenia echinococcus of the dog, and is common in the 
liver of the ox, sheep, pig, and many wild animals. It 
may also occur in the lungs, heart, kidneys, and brain, 
in the intermuscular connective tissue, or in almost any 
organ or tissue. 
The cyst takes six months to fully develop, and may 
range in size from a pea to a pumpkin. It possesses 
two layers—an outer thick envelope, known as the 
ectocyst, and an inner thin layer, the endocyst. The 
fluid contained is clear and serous, but free from albumin. 
Many are sterile, and contain no scolices. 
Echinococcus cysts may be single or multiple, from 
external or internal budding. The latter method is 
commoner in man than in the Herbivora. 
A liver thus infested is more or less enlarged, according 
to the number of cysts present. A hundredweight is 
not an uncommon weight for a badly affected ox-liver, 
and in this there may be present several thousand cysts. 
A pig’s liver may reach half this weight. The liver 
in these advanced cases is usually found firmly adherent 
to the neighbouring organs, such as the intestines, or to 
the diaphragm or omentum. On section the tissues 
may appear to be one mass of cells, resembling a honey- 
