134 PEOF. OWEN ON NEW A^B EAEE CEPHALOPODA. 



Suborder BECAPODA, Leach \ 

 Fam. SEPIAD^, Owen^ 



Genus Sepia, Lamarck ^ 



Species Sepia palmata, Ow. (Plates XXIV. and XXV.) 

 Of the present species the name relates to the great extension of the interbrachial 

 webs (ib. fig. 1, «, a), to which the nearest approach seems to be made by Sepia 

 orbignyana, Ferussac S and Sejiia elegans, d'Orb.^ but in so feeble a degree that their 

 presence is not noted in the text (pp. 273, 280), or shown in the plates "(Seiches) 5 and 

 8 ;" the degree in which such webs are developed in these species, however, is given in 

 a subsequent plate, below cited, where an oral view of the head, with arms outstretched, 

 exhibits the slight development of the basal webs m each of the species. 



The second specific character of Sej)ia palmata is shown by the fins (ib. o, d), which 

 not only commence at the fore part of the body, but extend in advance thereof almost 

 to the degree of the medio-dorsal production of the mantle ; the fins are also produced 

 further back than usual, and coalesce (o') beyond the end of the body '"'. In Sepia lati- 

 manus'' the fins terminate near the pointed end of the body and leave no notch, but do 

 not unite together. 



To the relative jn'oportion of the body to the head with its " corona," in which 

 character the Cuttles come nearer than the Squids to the Poulpes, Sepia palmata adds a 

 development of the interbrachial webs equal to that in Octopus vulgaris and the species 

 last described (PI. XXIIL). But the web is not continued in S. palmata between the 

 arms of the fourth pair. These, however, develop a narrow fold of the integument 

 from the outer and hinder surface (PI. XXV. fig. 1, «'). The arms decrease in length from 

 the 4th to the 1st, but in a very slight degree from the 4th to the 3rd. The acetabular 

 surface supports four rows of suckers, in the usual alternate relative position. The 

 suckers are small, rather more than hemispheres in shape, supported each by a peduncle 

 attached to one side of their " pole " and giving them an oblique position. The acetabular 

 cavity is small in proportion to its muscular walls, and is lined next its outlet by a broad 

 corneous hoop, the free border of which is finely denticulate. The interbrachial webs 



' "Cephalopoda decapoda," Zoological Miseellauy, iii., 1817. Trihus Decapoda, Trans. Zool. Soc. vol. ii. 

 (1811), p. 129. 



= Trans. Zool. Soc. vol. ii. (1841), p. 129. = Syst. des Anim. sans Vertcbres, 1801. 



* Hist. Nat. des CVphalopodes, fol., 1835-1848, p. 273 (Seiclies), pi. v. and id. xxvii. figs. 1, 2. 



' Ibid. p. 280 (Seiches), pi. viii., and pi. xsvii. fig. 5. 



" The terminal notch between the side fins is so common in the species of Seina that d"Orbigny makes of it 

 a generic character : — " Nagcoires — commenijant a la partie antcrieure memo du corps, ou au moins a tres pcu 

 de distance ; le bordant late'ralement sw touto sa longueur, en laissant entre elles, en arricre, une forte 

 echancrure " {op. cit., p. 250). 



' Op. cit., Seiches, pi. xii. fig. 1 ; Quoy ct Gaimard, Zool. de TAstrolabe, Atlas, MoUusipcs, pi. ii. figs. 2-11 . 



