Class CEPHALOPODA, Cuviee. 



Siphonopoda, Lankestor. 



Order I. DI BRANCH lATA, Owen. 



Suborder I. OCTOPODA, Leach. 

 Division 1. Lioglossa, Liitken. 



Family I. P T E R o t i, Reinhardt et Prosch. 



CiEP.OTEDTHiD^, Kefeistein. 



Cirroteuthis, Eschricht. 



Sciadephorus, Eeinhardt et Prosch. 

 Bostrychoteuthis, AgassiZj 



The history of this genus has been rather remarkable. Founded iu 1836 by 

 Eschricht for the reception of a single species, it underwent no enlargement for nearly 

 fifty years, until, in fact, the dredgings of the " Talisman " gave Dr. Fischer materials 

 for the description of a second species ; whilst during the past year no less than five 

 additional forms have been added, three obtained by the Challenger and two by the 

 U.S. steamer " Albatross." 



This sudden increase in our knowledge of the genus is coincident with the extensive 

 prosecution of deep-sea dredging, and, as will be explained in the sequel (p. 231), 

 furnishes one argument for regarding Cirroteuthis as an abyssal genus. 



It is of course possible that some two or more of these forms may belong to the same 

 species, for at present we have but slender means of ascertaining the amount of variation 

 in this genus. As specific characters I have relied upon the form of the internal 

 cartilage, the presence or absence of an " intermediate web," the position on the arm at 

 which the cirri commence and cease, and the presence or absence of a tubercle or in- 

 durated tract at the junction of the web with the arms, which will be described further on. 



Desiring to avoid as far as possible the danger of creating unnecessary species, I sent 

 drawings and descriptions of those proposed to Dr. Paul Fischer for comparison with his 

 type specimens, concerning which he writes, — " J'ai compare avec soin vos figures avec 

 les types de Cirroteuthis umhellata, et aucun d'eux ne se rapporte a mon espece, dont 



