293 
On Certain Cystic Worms, t See. By G. M. Giles. 
set up the patch of tissue reaction which forms the tubercle, and 
which doubtless persists until the complete breaking down and 
solution of the tissues of the dead intruder puts an end to the cause 
of irritation. Of the enormous numbers of cestode embryos that 
must often gain access to the solid organs of ruminants, only a very 
small percentage ever survive to develope into viable cysticerci, and 
the few that do never give rise to appearances at all comparable with 
the peculiar lesion now described. The use of the term cestode 
tubercle ” is not without precedent in the writings of Leuckart and 
others, but, so far as I am aware, the above explanation is now 
advanced for the first time. 
As already remarked, I am doubtful as to the precise species 
which is responsible for this condition. At this stage, one cestode 
embryo is pretty much like another, and the particular species of 
cysticercus into which it is going to develope is more a matter of 
conjecture than anything else. It may, however, be taken as toler- 
ably certain that the adult worm is a canine parasite. Now, as far as 
a limited number of examinations go, the taeniae found in dogs in this 
part of the world are Taenia cucumerina, T. litter ata, T. marginata, 
and T. echinococcus; of these four T. cucumerina , though by far 
the most common, may he left out of consideration as its intermediate 
hosts are, as is well known, canine skin parasites, Trichodectes canis 
and. as has been more lately shown by Sonsino, Pulex serraticeps * 
Taenia marginata may also be easily excluded, as the peculiar burrows 
characteristic of recent in ection by the embryos of that species, and 
well figured by Curtice, f were entirely absent from the cases under 
discussion. 
Of the intermediate host of T. litter ata, so far as I know, nothing 
is known, and as this species is commonly enough found in large 
masses in the pariah dogs here, there is no particular reason why 
this species should not be the culprit. It is indeed only the close 
microscopic resemblance of the embryos to the known embryos of 
compound echinococcus cysts, that leads me to give preference to the 
probability of their being referable to the last-mentioned species. 
One consideration that remains is that, putting aside the hypotheti- 
cal T. tenella of Cobbold, none of the cysticerci proper to sheep belong 
to species parasitic in the adult stage in man, and hence no possible 
risk can be involved in the consumption of meat affected in this way. 
The nematode tubercles were found exclusively in the livers of 
mules and horses, and must be tolerably common in Assam as they 
were observed twice in the half dozen or so examinations made there. 
Since then I have had no further opportunities of examining equine 
animals, and so have no knowledge how far they may be common in 
other parts of India. Close as is their naked eye resemblance to the 
* Sonsino, ‘ Rieerche sugli ematozoi del cane e sul ciclo vitale della tsenia 
cucumerina,’ Pi?a, 1888. 
t Curtice, 4 Animal Parasites of Sheep,’ Washington, 1890, p. 80. 
