250 Proceedings of the Eoyal Physical Society. 



bauds in the interval between the publication of the JEssai (1880) and 

 that of the Supplement (1885). Consequently Docophorus bassance, D., was 

 included by Kellogg in his list of Mallophaga (1908). 1 



7. One further point may be mentioned. On the postero-ventral aspect 

 of the tarsus of pullatus (well seen on the mid and hind legs) is an almost 

 apical group of peculiar broad spines which are slightly hooked at the 

 end. These, somewhat less developed, reappear in bassance. 



While examining this material from Sula bassana it occurred to me to 

 make a comparison with a long series of Lipeurus from a " Booby Bird " 

 (Sula sp.) from Christmas Island. This is a large form, perhaps new, 

 closely related to L. annulatus, P., and L. pullatus, N. Here again one 

 finds a bassa?ice-\ike juvenile stage. The tarsal hooks (see 7 above) are 

 replaced by stout, straight bristles, and the juvenile changes in this respect 

 also. 



It would seem then that D. bassance, D., and L. staphylinoides, D., are 

 conspecific with L. pullatus, N. 



Mr Wm. Evans, in recording (Ann. Scot. Nat. Hist., 1906, p. 87) the 

 occurrence of both sexes of L. staphylinoides, D., from St Kilda, made the remark 

 that the females bore a close resemblance to Denny's figure of his Docophorus 

 bassance. I find on inquiring that Mr Evans had then reached the above 

 conclusion, though he did not publish his result. I am glad to have the 

 support of his valuable opinion in a matter where accuracy is so desirable. 



1 Kellogg, in Wytsman's Genera Insectorum, 66 me - Fascicule, " Mallophaga," p. 10, 

 species 25. Kellogg gives as host, "Sula bassana (Great Britain) and the Gannet 

 (United States of America)," so that the duplication of pullatus must exist in the 

 American literature also. 



tssued separately, 9lh April 1912.) 



