ENTOZOA FROM THE AUSTRALIAN HAIR SEAL. By T. Harvey Johnston, Professor of Zoology, University of Adelaide. (Tvsrelve Text-figures.) [Read 31st March, 1937.] In January, 1923, Professor F, Wood Jones, F.R.S., led a small biological party which visited Pearson Island, lying about twenty-five miles off the west coast of Eyre's Peninsula, South Australia. Amongst the material obtained were some entozoa collected by Professor J. B. Cleland from the Australian hair seal, ArctocejJhalus forsteri (Lesson). No species of parasite has, as yet, been recorded from our pinnipeds. Amongst the ectozoa known to occur on the hair seal may be mentioned a Pediculid, probably an undescribed species of Antarctophthirius or Echinophthirius. The entozoa referred to in this paper belong to three species, namely, a cestode, Diphyllobothrium arctocephalinum, n. sp.; a nematode, Contra-caecum osculatum (Rud.); and an echinorhynch, Corynosoma aiistrale, n. sp. The types of the new species have been deposited in the South Australian Museum, Adelaide. DlPHYLLOBOTHRIUM ARCTOCEPHALINUM, U. Sp. FigS. 1-7. In the intestine of Arctocephalus forsteri there was found a tangled mass of cestodes whose separation resulted in some fragmentation. A specimen bearing a scolex was 17 cm. long, the terminal 5 centimetres bearing eggs. A fragment of another strobila was about 44 cm. in length, approximately 40 cm. of it being ovigerous. If one matched these two fragments according to the sizes of their segments and their reproductive condition, the total length of an unbroken strobila would be not less than 54 cm., of which more than 40 cm. would probably be egg-bearing. Segments which had just become ovigerous were nearly one milli-metre long and 5 mm. broad, and sufficiently overlapping the succeeding proglottis to give a slightly serrate margin to the strobila. In strongly contracted strobilae the serrations were much more pronounced. Segments in the mid-region of the scolex-less sti'obila, mentioned above, were about 5 mm. wide and 2-5 to 3-1 mm. long, whilst those near the posterior end measured 6 mm. in width by 3-7 mm. in length. Another fragment, 36 mm. long, possessed a markedly crinkled margin and x^ all its segments were egg-bearing, but they were considerably wider and shorter anteriorly, 6 mm. and 1-5 mm. respectively, than in the corresponding portion of the other strobila. The length gradually increased to 3 mm. in segments at the end of specimen, the breadth becoming 8 mm. Hence, at first sight, there appeared to be two species represented in the material, but the anatomy was similar and the differences in dimensions were due no doubt to the state of muscular contraction. The scolex was narrower than the succeeding segments, but, when viewed laterally, was seen to be at least twice as thick as the neck region. The dimensions varied according to the state of contraction. When relaxed the breadth was F
BioStor
