[161] CEPHALOPODS OF NORTHEASTEPtN COAST OF AMERICA. 371 



5. The sperrnatophore sac (ss) is a long, capacious, pyriform, or some- 

 what fusiform, thin-walled sac, pointed at its posterior end ; its anterior 

 end is directly continuous with the long efferent duct (p), which is often 

 rather wide at its origin but tapers to a narrow anterior end. The ter- 

 minal orifice is slightly bilabiate. 



These organs receive blood through a special artery (fig. 2, po) which 

 arises from the posterior aorta just back of the heart. Aftei reaching 

 the genital organ it divides into several branches; one going forward 

 along the side of the efferent duct; one to the prostate glands and 

 vesiculce-seminales; one to the vas-deferens and adjacent parts. 



Specimens taken in May, in the breeding season, have the efferent 

 duct and the spermatophore-sac crowded with the sperm atophores. In 

 the spermatophore-sac, which is then much distended by them, they lie 

 closely packed in a longitudinal position with their larger ends pointing 

 somewhat outward toward the surface, and can be plainly seen through 

 the transparent walls of the sac. 



The sperm atophores are slender, club-shaped, with the larger end 

 rounded, tapering gradually to the smaller end, which is usually a little 

 expanded at the tip and has a very small filament. They vary (in al- 

 cohol) from 8 to 10 mm in length and 4 to 5 mm in the greatest diameter. 

 They contain a coiled rope of spermatozoa in the larger end and a com- 

 plicated apparatus for automatically, ejecting this rope in the smaller 

 portion. 



The "testicle" or spermary (t) is a compact, pale yellow, long, flat- 

 tened organ, extending from the stomach (s) nearly to the end of the 

 pen, in the posterior concavity of which it lies; a band of fibrous tissue, 

 continuous with its sheath, extends from its posterior end into the hol- 

 low tip of the pen, to which it is attached. An arterial vessel, the sper- 

 matic artery (PI. XL, fig. 2, go), which arises directly from the anterior 

 edge of the heart, runs along the median dorsal line of the spermary 

 and sends off numerous branches to the right and left (fig. 2, t). This 

 artery is accompanied by a spermatic vein (sv), closely united to it. 



Loligo brevis Blainville. 



Loligo brevis Blainv., Jonm. de Phys., March, 1823 (t. D'Orb.); Diet. desSci. 

 nat.,vol. xxvii, p. 145, 1823. 

 D'Orbigny, C6phal. Ace"tab., p. 314, Loligo, pi. 13, figs. 4-6 (copied from 



Lesueur); pi. 15, figs. 1-3 (orig.); pi. 24, figs. 14-19 (orig.). 

 Tryon, Marine Conch., i, p. 142, pi. 52, figs. 143, 144 (after D'Orbigny). 

 Verrill, Trans. Conn. Acad., v, p. 343, 1881. 

 Loligo brevijpinna Lesueur, Journ. Acad. Nat. Sci. Philad., vol. iii, p. 2^2 (with 

 plate), 1824. 

 Tryon, Manual Conch., i, p. 142, pi. 51, figs. 128-130 ( after Lesutur). 



Plate XXI, figures 4-4c. 



A small, short-bodied species, with short rounded caudal fins, very 

 short upper arms, and large chromatophoric spots. 

 Body short, thick, well rounded, rather blunt posteriorly. Anterior 



