A. E. Verrill — JVorth Aynerican Ceplialopods. 429 



three ; the lateral ones are usually T-shaped, I'ormed by a longitudinal 

 ridge, with a smaller transverse one across its posterior end ; the 

 corresponding cartilages on the siphon are long-triangular, with a 

 longitudinal and a transverse groove. Two oviducts. Hectocotylized 

 arm of tlie male may be either the right or left ventral. 



Pen usually very narrow along the middle portion, and with three 

 ribs; anterior and posterior portions expanded, the latter with the 

 edges involute, and forming a terminal hood or hollow cone. 



Ommastrephes (See pp. 267, 385). 



Ommastrephes {iMrs) D'Orbigny, Yoy. Am. Merid., 1835 ; Cephal. Acetab., p. 341. 

 Illex and Todarodes Steenstrup, Oversigt k. Danske Videnske. Selsk. Forhand., 1880, 

 p. 90. 



2. Ommastrephes illecebrosus (Les.) Yemii. (pp. 268, 403). 



Sthenoteuthis Yerrill. (See pp. 222, 286, 385, 402). 



Ommastrephes (pars) D'Orbigny, Yoy. Amer. Merid., Moll.. (1835 ?) ; Ceplial. Acetab., 



1839-'48. 

 Sthenoteuthis Yerrill, Trans. Conn. Acad., vol. v, p. 222. Feb., 1880; Amer. Journ. 



Sci.. vol. xix, p. 289, April, 1880. 

 Ommastrephes Steenstrup, OyeTs\gt k. Danske Yidensk. Selsk. P^orhandl., 1880, p. 



89 (sep. cop. p. 19, received Aug., 1880). 



3. Sthenoteuthis megaptera Yerrill. (pp. 223, 286). 



Sthenoteuthis pteropUS (Steenst.) YerriU. (pp. 228, 402). 



4. sthenoteuthis Bartramii (Les.) Yerrill. (p. 2S8). 



ArchiteuthlS (Steenst.) Harting, 1881. (See pp. 197, 259, 394, 422). 

 Architeuthus Steenst, 1856, (no description). 



5. Architeuthis Harveyi Yerrill. (pp. 177-210, 259, 395, 422). 



6. Architeuthis princeps Yerrill. (pp. 181-189, 194, 259). 

 Architeuthis monachus (Steenst.) (pp. 238-245). 



Architeuthis dux (Steenst.) Gervais. (pp. 238-240). 



Architeuthis Hartingii Yerrill. (p. 240). 

 Architeuthis Bouyeri Yerrill. (p. 243). 

 Architeuthis (?) Mouchezi Yeiain. (pp. 243, 398). 



Architeuthis grandis (Owen) Yerrill. (p. 400), 



