[125] CEPHALOPODS OP NORTHEASTERN COAST OF AMERICA. 335 



Arms with depressed suckers. Tentacular arms with a well-developed 

 club, bearing suckers. 



DBSMOTEUTHIS Verrill. 



Taonius (})ars) Steenstrup, 1861. 



Desmotcuthis Vervill, Trans. Conn. Acad., vol. v, p. 300, Feb., 1881. 



Body very long, tapering backward to a long, slender, acute caudal 

 portion. Caudal tin long, narrow, tapering to a long, acute tip. Anterior 

 edge of the mantle united directly to the head, on the dorsal side, by a 

 commissure, so that there is no free edge medially, and the surface is 

 continuous, as in Sepiola; the dorsal commissure extends backward and 

 diverges within the mantle 5 two additional muscular commissures unite 

 the lateral inner surfaces of the mantle to the sides of the siphon. 

 Eyes very large and prominent, with simple circular lids. ISTo aquiferous 

 pores. Siphon large and prominent, with neither valve nor dorsal bri- 

 dles. Arms small and short, subequal, with a basal web and lateral 

 membranes; suckers smallest on the ventral arias, and urceolate, largest 

 and flatish on the middle of the lateral and dorsal arms, feebly toothed. 

 Pen extending the whole length of the body, very slender and of uni- 

 form width for more than half the length, then becoming broad-lanceo- 

 late, the terminal portion having the edges involute, forming a long, 

 slender cone, into which the ovary extends. Mdamental glands large, 

 symmetrically developed on the two sides. Gills small, situated in front 

 of the middle of the body. 



The genus Taonius was proposed by Steenstrup to include this and 

 T. pavo (Les. sp.), but he has not, to my knowledge, definitely defined 

 the genus. As T. pavo appears to be generically distinct from the pres- 

 ent genus, I propose to retain Taonius, with T. pavo for its type. By 

 many writers T.pavo has been placed in Loligopsis or Leacliia. Steen- 

 strup himself formerly referred _D. hyperborea to Leacliia. By Tryon 

 both have been referred back to Loligopsis. 



Loligopsis, as defined by D'Orbigny, in 1839, included T. pavo, as well 

 as the type of Leacliia, but he referred Lamarck's original tj^pe of Loli- 

 gopsis to the genus, as amended by him, only with doubt. 



It seems desirable, therefore, to explain this confusion, so far as pos- 

 sible. 



Loligopsis Lamarck,* 1812 and 1822, was based only on an imperfect 

 figure, made by Peron, of a small oceanic squid which had lost its ten- 

 tacular arms. The supposed character of having eight arms was, for 

 him, the only basis for the genus, no others being mentioned. The 

 species (L. Peronii) was, however, described very briefly as a small squid 

 with eight equal arms and two posterior, distinct caudal fins, and it was 

 compared to Sepiola. It has apparently not been rediscovered by later 

 writers, unless L. chrysoplithalma D'Orb. be the same species, which is 

 quite possible. The latter, as figured, is a small, short-bodied species, 



*Extr. do Corns de Z00L, p. 133, 1812 (t. D'Orb.); Animaux sans Vert., vol. vii, p, 

 659, 1822. 



