CHESTODA. 
By Arruur E. Surpriey, M.A., F.R.S., 
Fellow and Tutor of Christ’s College, Cambridge, and University Lecturer in the 
Advanced Morphology of the Invertebrata. 
(1 Plate.) 
THE only Cestodes brought back by the naturalists of the ‘Discovery’ were three species, 
all of which were found living together in the stomach of Ross’s Seal, Ommatophoca 
rossi. The three differed markedly in size, in the shape, number and relative pro- 
portions of the proglottides, so that there is no doubt that we are dealing with three 
distinct species, and not with different stages in the growth of members of one species. 
All the specimens were pickled in Perenyi’s fluid, and arrived in an excellent state 
of preservation. ; 
The largest of the three species is undoubtedly the same animal which Baird, in 
1853, named Bothriocephalus antarcticus. 
I give below Baird’s diagnosis, and then add a few remarks upon the anatomy of 
the specimens. 
DIBOTHRIOCEPHALUS ANTARCTICUS. 
Bothriocephalus antarcticus Baird, Proc. Zool. Soc. London, 1853, p. 25, Annulosa, pl. xxxi., fig. 4 and da. 
‘* Head conical, elongated, smooth, with two lateral opposite fossettes. At the lower 
margin of each fossette there are two small rounded projecting lobes. Body rounded ; 
from the neck some way downwards it is quite round or cylindrical, and the articulations 
are very numerous and very small, appearing like mere ridges across. Lower down, the 
body becomes flatter and the joints larger and more developed; lower margin thin. 
An impressed line runs along the centre of the body through its whole length. Length, 
about 9 inches; greatest breadth of body, about 3 lines.” 
Baird’s specimens measured about 9 inches, say about 23 cms. Most of the 
specimens at my disposal were just under 10 cms., but a couple, apparently young, 
barely measured 3 cms. The specimens were obviously immature, only in the 
most posterior of the longer examples were uteri and ova to be found, and the 
latter in very small numbers; I am inclined to think also that these specimens 
had contracted when being killed, the anterior end of the body not being so 
rounded as Baird describes. The greatest breadth is 7 mm. in the largest specimen. 
Z 2 
