166 DR. T. S. COBBOLD ON ENTOZOA. 
ments, and I therefore regret that cireumstances have prevented my carrying out more 
fully an intention of verifying some of those particulars which have recently attracted our 
notice. Two of a few experiments, however, having been completed and attended with 
partially satisfactory results, I take this opportunity of placing them on record :— 
On the 5th of February, 1856, I administered to a Dog three minute Cysticerci, obtained 
from the fresh livers of two wild Rabbits. These eysts were perfectly round and measured 
only the twelfth of an inch in diameter, and were evidently not to be referred to the 
common C. pisiformis. A fortnight after (19th) six similar cysts were obtained from 
the liver of another wild Rabbit and given to the same Dog. Ten days subsequently the 
canine animal was destroyed by chloroform, when, on laying open the small intestines, six 
specimens of Tenia cucumerina were detected. Three of these individuals were severally 
about 12 inches in length, the others measuring only 3 inches. Thus far, therefore, 
but for the circumstance of three of the nine cysts administered being undeveloped or lost, 
no doubt whatever could be entertained as to the complete success of this experiment. 
As it is, we bave the interesting result of three nearly completely developed tape-worms, 
the growth and number of which exactly correspond with the circumstances that ap- 
parently led to their presence in the viscera of the Dog; and in addition we have three 
other individuals, only one-fourth of the bulk of the former, which may legitimately be 
regarded as the partially developed representatives of three of the six Cysticerci that were 
subsequently administered. It would appear, in consequence of the C. pisiformis being 
frequently present in the liver of the Rabbit, as well as in the mesentery, that our minute 
Cysticercus has not hitherto been recognized as distinct; at least, I find no notice of it in 
foreign works, and shall therefore in future speak of it as C. cueumerinus. In order to im- 
part additional value to the above experiment, a young tame Rabbit was next procured, 
and the three larger Tænias (whose caudal proglottides contained multitudes of imper- 
fectly formed ova) were given to it, the living worms being greedily devoured with portions 
of a cabbage-leaf. Eleven days after, the Rabbit was destroyed, and the liver found to 
contain numerous minute cysts corresponding to those of C. cucumerinus, the great omen- 
tum likewise containing four specimens of C. pisiformis. No inference of any value can 
be deduced from the presence of both kinds of Cysticerci in this case, for they are almost 
always present in tame Rabbits, young or old, whether they have eaten tape-worms or not, 
On the same day, 11th March, portions of the liver were given to a young Dog, and on the — 
17th many examples of C. pisiformis from the omentum of another tame Rabbit were 
given to the same animal. Two or three days before the second worm-feeding, this dog 
had commenced ejecting its ordinary food, and I have no doubt that by far the greater 
part of the more recently introduced worm-feedings shared the same fate. This throwing — 
up of the stomachal contents was followed by total abstinence; and as the dog appeared 
weak, it was accordingly destroyed on the 20th, thus allowing only three days for the 
development of any pisiform Cysticerci that might chance to be retained, and but nine — 
days for the small liver-cysts. The result was as follows :—Seven tape-worms were pre- —— 
sent in the intestine; of these, four were specimens of Tenia cucumerina, varying from a 
to 10 inches in length, and the remaining three were examples of T. serrata, the segmen- — | 
tation of which was scarcely manifested, the longest individual measuring less than an 
