110 THE TOYAGE OF H.M.S. CHALLENGER. 



Length of first arm/ 

 Length of second arm, 

 Length of third arm, 

 Length of fourth arm, 



Eight. 



Left. 



26 mm. 



27 mm. 



27 „ 



23 „ 



36 „ 



30 „ 



26 „ 



26 „ 



The genus Japetella was originally created for the reception of two forms, which 

 however, differed in a character so important that they were only united provisionally. 

 Since then the other species {Japetella diaphana) has been referred to Eledonella, 

 Verrill, so that the present genus is monotypic. The distinguishing character is the 

 median ventral septum in the branchial cavity, which, though present in Octopus, 

 Eledone, Cirroteuthis, Eledonella, and Bolitsena, is absent in Japetella. The presence 

 of a valve in the siphon is very remarkable. 



This is another of the forms brought up by a trawl which had been down into 

 deep water, and concerning whose real place of origin there is considerable uncertainty; 

 its general similarity to Eledonella is so great that whatever decision is come to regard- 

 ing the one, must be regarded cl priori as probably true of the other. 



Suborder II. DECAPOD A, Leach. 



Division I. MYOPSIDA, d'Orbigny. 



Family VII. Sepiolini, Steenstrup. 



Sepiola (Rondelet), Leach. 



Sepiola rondeleti. Leach. 



1558. Sepiola rondeleti, Gesner, De Aquat., lib. iv. p. 855. 



1817. ,, Rondeletii, Leach, Zool. MisceU., vol. iii. p. 138. 



1839. „ „ d'Orb., C(^ph. acet., p. 230; Sepioles, pL i. figs. 1-6; pi. ii. figs. 3-13 ; 



pi. iii. figs. 6-9. 

 1845. „ oceanica, d'Orb., MoU. vivr., pi. x. fig. 13 (e?T.). 



1853. „ Rondeletii, Forbes and Hanley, Brit. Moll., voL iv. p. 220, pL mmm. fig. 1. 

 1869. „ Rondeletii, Targ., Cef. Mus. Firenze, p. 45. 

 1869. ,, Rondeleti, Jeffreys, Brit. Conch., vol. v. p. 136. 

 1879. „ sepiola, Tryon, Man. Conch., vol. i. p. 155. 



Habitat. — The Minch, west coast of Scotland, "Porcupine" Expedition, 1869; 

 60 to 80 fathoms. Two specimens, $ . 



British Seas (Forbes and Hanley, Jeffreys); Atlantic coast of France (Fischer, 



1 The lengths of the arms are measured from the eye. ^ Mutilated. 



