226 " ENDEAVOUR " SCIENTIFIC KESULTS. 



the same. It is already known to be very widely distributed, 

 and the details given for H. benthaliana seem to me scarcely 

 sufficient to distinguish it from Muller's species. 



It appears from the various accounts that the relative 

 lengths of the three middle tentacles is subject to variation. 

 By some authors they are described or shown as approximately 

 ec(ual, while others give a greater length for the median, as, 

 for example, Ehlersi. Again, the size of the worm, the 

 position of the first gill, the number of denticulations on the 

 jaw jjlates, show a fair range of variability. 



In the present case it may be as well to record the facts. 

 The filamentous gill commences on the 2?nd chfctigerous 

 segment. The jaw plates of the second pair (II) on the right 

 side bear 11, on the left 12 denticulations ; IV have 8 and 9 

 or 10 respectively ; the unpaired one has 13. 



The present worms agree more closely with the typical 

 form as described by M'Intosh and St. Joseph^ than with 

 any of the " varieties " described by the former author ; 

 especially in the denticulations of the jaw plates as well as in 

 the segment on which the gills commence. 



Loc. — Off Babel Island, Bass Strait, 50-80 fathoms. 



Distribution. — ^The typical form and its " varieties " have 

 been obtained in the European seas ; in the Atlantic ; from 

 the Pacific ; on the coast of Japan (Moore)^ and of California 

 (Moore)* ; from New Zealand (Ehlers)^ ; from Torres Strait 

 (MTntosh). I have no literature dealing in detail with other 

 regions. 



It has already been suggested by \\ illey^ that H. ccmii- 

 guitia, Grube'7, from the ir'hilippiaes, Ceylon and the Indian 

 Ocean (Crossland)® is merely "' a local form '" of the European 

 species, and it seems not unlikely that H. brevicirris, Grube,^ 

 from Moreton Bay on the east coast of Australia is ako a 

 variety of this species, for the account only differs in one 

 or two features of proportions of parts. If these two be 

 included, then the species may be said to be distributed 

 everywhere outside the Arctic and Antarctic seas. 



1. Ehlers— Die Borstemviirmer. ]8fi4-fiP, p. 297. 

 •2. St. Joseph— Am. Sci. Nat., (8), v., 1898, p. 241. 



3. Moore- -Proc. Atad. Nat. >Sci. Philadelphia, 1903, p. 444. 



4. -Moon — Loc. ciL, 1911, p. 280. 



5. Ehlers Neuseeland. Annelid., 1907. p. ID. 



6. Willey — Cejdon Pearl Oyster Fisheries, pt. iv., Suppl. Rep., xxx., — 

 Polvehaeta" 1905, p. 274. 



7. Grube — Annulata Semperiana. 1878, p. 42. 



8. Crossland— Proc. Zool. Soc., 1904, p. 281. 



9. Grube — Monatsber. Akad. Wiss. Berlin, 1877, p. 528. 



