1862.] DR. T. S. COBBOLD ON HUMAN ENTOZOA. 313 
of sufficient value for specific separation. Like Dujardin, I have not 
seen the head of 7’. elliptica, neither am I acquainted with any good 
figure of the head*. Goeze’s drawings of 7’. cateniformis only repre- 
sent a single row of little hooks ; and it is well known that the same 
processes in 7’, cucumerina are very liable to fall off, so much so 
that it has been described as a hookless tapeworm. Van Beneden 
regards the two presumedly distinct forms as identical, and, although 
his representations of the cephalic hooks of 7’. canina correspond 
very closely with those of the 7’. cucumerina, both of Dujardin and 
Leuckart, he speaks of three or four rows of hooks, whilst Dujardin 
says there are three, and Leuckart simply describes a succession 
(“ mit einer mehrfachen Reihe”’ ), though his excellent figure (fig. 118, 
p- 400, of his work) represents four ; he also describes three or four 
rows as occurring in 7’. elliptica. It is therefore evident that varia- 
tions occur in the same form as regards the head; and it is more 
than probable that differences of habitat may be sufficient to account 
for the variations of size and numerical development of the joints, 
which Leuckart regards as distinguishing marks between the elliptic 
tapeworm of the cat and the cucumerine cestode of the dog. Be 
this as it may, one or other of these forms has been noticed in the 
human subject several times; but as regards the source of their 
larvee we are yet in uncertainty. When engaged (1856) in rearing 
Tenia serrata from Cysticercus pisiformis, | thought I had also hit 
upon the scoleces of 7’. cucumerina ; but Leuckart has since extended 
my experiment by feeding rabbits with the proglottides of 7. eucu- 
merina, without producing any measles. Van Beneden has also tried 
to produce the young of Tenia elliptica in the rat, but without 
result. Weinland thinks the Cysticercus of JT’. cucumerina will be 
found in flies, and that dogs obtain the larve by their interesting 
habit of snapping at dipterous insects. This is, at least, ingenious. 
29. BoTHRYOCEPHALUS LATUS, Bremser. 
B. latus, Bremser, Blainville, Leblond, Rudolphi, Leuckart, 
Nitzsch, Mehlis, Chiaje, Owen, Creplin, Haselberg, Siebold, Esch- 
richt, Valentin, Wawruch, Dujardin, R. Leuckart, Kiichenmeister, 
Leidy, Weinland, &c. &e. 
Dibothrium latum, Diesing. 
? Tenia lata, Linneus, Pallas, Bloch, Goeze, Batsch, Gmelin, 
Schrank, Carlisle, Jordens, Rudoiphi. 
?T. vulgaris, Linneeus, Werner, Retzius, Gmelin, Jordens. 
T. dentata, Batsch, Gmelin. 
* I have now (Jan. 27, 1863) procured several heads of 7. elliptica, and am 
still unable to pronounce the two forms to be distinct species.—T. S. C. 
t In connexion with these views of Weinland and Leuckart, I may here men- 
tion that I have recently been feeding a number of cockroaches (Blatta orientalis) 
with the eggs of Tenia cucumerina of the dog, but I have not succeeded in rear- 
ing any Cysticerci in their bodies. Not discouraged by negative results (which 
often advance our science as much as positive ones), I shall presently feed them 
with the eggs of T. elliptica from the cat; and if I should succeed in thus giving the 
cockroaches the ‘‘ measles,” I shall have less hesitation in pronouncing Leuckart’s 
opinion, as to the distinctness of these two tapeworm-forms, correct. 
