154 A REPORT ON THE SIPUNCULOIDEA, COLLECTED BY DR WILLEY 



This species is also described from the Mauritius and the Philippines, and a 

 specimen of what I take to be the same species was brought home by Professor Weldon 

 from the Bahamas. 



5. Aspidosiphon truncatus Keferstein. (III.) 



Two specimens found in Sandal Bay, Loyalty Islands. This species is recorded 

 from the Mauritius and from Panama. 



II. Genus. CLOEOSIPHON, Quatrefages. 



6. Cloeosiphon aspergillum Quatrefages. (VII.) 



Numerous specimens, some imperfect, from Sandal Bay, Lifu, Loyalty Islands. This 

 species is registered in Selenka's Monograph from Caminguin, Uhoy ; Zamboango ; 

 Luzon ; Mauritius ; Ibo and the Viti Islands, and by Dr W. Fischer 1 from Thursday 

 Island, Samoa, and off the East African coast. 



An examination of the specimens brought home by Dr Willey affords a good 

 example of the difficulties of systematic work amongst the Sipunculids. His specimens 

 fall readily into two groups, one with a thin transparent skin, of a uniform gray 

 colour, with no apparent papillae, the other of individuals with thick opaque skins, 

 harsh to the touch and with papillae just visible to good eyesight. The members 

 of this latter group are not always uniform in colour and are for the most part either 

 deep yellow or brown. Here I thought are two distinct species. On opening the bodies 

 of one of each group, although the relative size of the organs varied owing to the 

 different states of contraction in which they had been when killed, I could detect no 

 real differences of structure corresponding with the differences of the external appearance. 

 I re-examined the skin with the aid of a lens and found that though few in number 

 there were some papillae in the transparent specimens, chiefly at the posterior end 

 but also round the base of the chalky ring. Finally I prepared specimens of the hooks 

 on the introverts of members from each group ; in colour, size and shape, the hooks 

 exactly resembled one another. There thus seemed no doubt that these two groups 

 although they differed externally to a very marked degree formed in reality but one 

 species. 



ILL Genus. PHASCOLION, (The"el) Selenka and de Man. 



7. Phascolion manceps Sel. and de Man. (VIII.) 



One specimen only was found, and this was so small that I had considerable difficulty 

 in making out the anatomical features. However, I have little doubt that this specimen 

 belongs to the species Phascolion manceps which Selenka and de Man described from a 

 single specimen taken in a Nassa shell in the Philippines (Uhoy). Dr Willey's example 

 was living in the shell of a young Mollusc named Astralium moniliferum Hed. and 

 Wil., which has been recently described 2 . The shell and its contents was taken in the 

 trawl off Man Island, Talili Bay, New Britain, in 35 fathoms. 



1 Loc. cit. p. 338. - P. Linn. Soc. N. S. Wales, Part I., p. 107. 



