:;n "TERRA NOVA" KXPKDITK >N. 



terminal position of the anus. the posterior situation of the vulva, and the production <>l 

 thirk-.sliellcil eggs. necessitate the separation of this form from the genus Filaria in its 

 modern acceptation. We regard the present species as the tvpe ol' a distinct genus, tor 

 which \ve liave proposed the name Crassicauda. 



ACANTHOCEPHALA. 



(. 'orynosoma, Liihe. 



8. < 'ari/iiaxiiiiiti li/iniiiinii (v. Linst.). (PI. II, tigs. 1 1, 12.) 



t> 



oTJiynchug Tiamanni, v. Linstow. 

 ('(ii'i/iiiixiniKi antaTcticum, Retmie. 

 EcMnorhynchus antarcticus, Rennie. 



,, xqilin, Ruilliet and Hemy. 



.sY.s'. These thorn-headed worms were found in considerable numbers in 

 Weddell's Seal, the (Vali-eating Seal, and the Sea-Leopard, attached firmly to the 

 mucous membrane of the small intestine. 



Parn*itt'. The parasites are pyriform and might in haste, lie mistaken for Amphi- 

 stomes. The rostellum (PL II, fig. 11, u) is partially sunken into the broader and 

 globular end, thus producing some resemblance to the ventral sucker of many of the 

 Paramphistomidae. The species was also found by the Scottish Antarctic Expedition, 

 and has recent! v been the subject of a monograph liy Dr. .lolm Uennie. With his 

 account our findings tally, save in three respects. 



(</) The number of hooks upon the rostellum is, according to our reckoning, 150 

 to 170, whereas Kennie states that there are about l'S rows, each having ten 

 hooks. 



A re-examination of the type-material of /'-. antarcticus sho\vs that this discrepancy 

 is probably attributable to a different mode of counting. Owing to their peculiar 

 alternating arrangement, the hooks may lie counted in a spiral fashion as well as in 

 vertical rows. 



(//) We have not found anv departure from the normal arrangement in the male 



genital system. 



As this has not Keen previously portrayed, it is illustrated in Fig. 1 I. 

 (r) In dealing with its systematic position. Rennie contrasts this form with allied 

 forms parasitic in aquatic birds. 



The species which Dr. Kennie regarded as new would appear to be even more 

 losely related to Echinorhynchus xcirK'nin' Forskal from /'hunt vitulina, and to be 

 svnonvmous possiblv with A\ luniniiiiii v. Linstow from \\eddell's Seal. In all three 

 forms the spines on the liodv extend along the whole of the ventral aspect and envelop 

 I he posterior extremity (PI. II. tig. 1 I. //). The number of longitudinal rows of hooks 

 in A,', semerme is slated to be twentv-lbur to twentv-six : A'. Linstow ^ives for 



