ii THE VOYAGE OF H.M.S. CHALLENGER. 



piece of work in my hands, and for the kindness and consideration with which he has at 

 all times assisted me in carrying it out. I am indebted also to Dr. Giinther and Mr. 

 Edgar A. Smith for facilitating my examination of the National Collection, and to the 

 latter gentleman in particular for notes and comparisons which he has been good enough 

 to make forme. In addition, my thanks are due to Professor E. Eay Lankester, F.E.S., 

 to Dr. Paul Fischer, and to my friend Dr. Georg Pfeffer for having courteously answered 

 a number of questions regarding specimens in their charge ; to Dr. Jatta of the Naples 

 Zoological Station ; to Dr. P. H. Carpenter, F.B,.S., for information regarding the cruise 

 of the " Porcupine"; to Dr. A. T. de Rochebrune for having shown me several of the 

 valuable type specimens in the Museum of the Jardin des Plantes ; and to Dr Murie, 

 the able librarian of the Linnean Society, for assistance in the bibliography of the subject. 



No ordinary acknowledgment, however, is sufficient to indicate the extent of my 

 obligation to my good friend Professor Steenstrup ; not only did he allow me during my 

 sojourn in Copenhagen the greatest freedom of access to the invaluable collection under 

 his charge, but also gave up many hours to assist me in the work of comparison, and 

 since my return he has been good enough to answer numerous questions regarding 

 points of uncertainty or confusion, and has read over the proofs of this Report, which 

 has thus been saved from many errors, which it must otherwise have contained. 



In addition to the Challenger collection the present memoir treats of those obtained 

 by H.M.SS. "Porcupine," "Knight Errant," and "Triton;" those from the two latter 

 expeditions were placed in my hands by Mr. John Murray, while the specimens collected 

 by the " Porcupine," which had been handed by the late Dr. Gwyn Jeffreys to Professor 

 Steenstrup, were transferred by him to me that they might be treated of along with the 

 others ; a few specimens from the " Valorous " Expedition were also received with 

 them. 



The present Report is almost exclusively systematic in its scope, but I hope to be 

 able within a year to prepare a Supplement giving an account of the anatomical exami- 

 nation of those specimens which are available for the purpose. 



The ten years which have now elapsed since the return of the Challenger, have 

 to some extent impaired the novelty of this Report ; in that interval marine zoological 

 investigation in general, and deep-sea dredging in particular, have been so energetically 

 prosecuted, that no less than five genera which were first collected by the Challenger have 

 been since described from other sources.-' 



1 AUoposzis, Eledonella, InioUuthis, Mastigotciithis, Calliteuthis. 



