184 Bulletin, Vanderoilt Marine Museum, Vol. IV 



In the smaller suckers the teeth are longer, slenderer and much more 

 acute. 



The tentacular arms are nearly as long as the body in living speci- 

 mens, slender, compressed, with a membranous keel along the outer 

 edge which widens on the club especially on its distal half. The 

 tentacular suckers are arranged in four rows, two median alternating 

 rows composed of seven or eight large, wide, depressed suckers on the 

 center of the club with several smaller ones at each end. Along each 

 margin alternating with the larger suckers there is a row of much 

 smaller, very oblique ones. On the proximal part of the club there are 

 few small, denticulated suckers; the distal part bears a great many, 

 very small, sharply denticulated, pedicelled suckers, crowded in four 

 rows ; those at the very tip are usually devoid of dentition. The large 

 suckers vary considerably in size according to age and sex. The 

 larger suckers are higher on one side than the other with a wide 

 aperture, encircled by a chitinous marginal ring which is divided all 

 around in sharp, unequal teeth, usually those on the outer side the 

 larger ; usually one small, very sharp tooth occurs between two larger 

 ones (fig. C) ; there is a wide soft basal membrane surrounding the 

 horny ring. The smaller suckers have the aperture more oblique 

 and the horny ring larger on one side with the outer marginal teeth 

 longer and more incurved, usually a larger tooth alternating with a 

 smaller one. 



The outer buccal membrane is large, thin, produced into seven 

 elongated acute angles, all of which have a cluster of ten to fifteen 

 small, pedicelled suckers, arranged in two rows; the chitinous ring 

 of these suckers is denticulated on one side. In adult females there 

 is also a horseshoe-shaped thickened organ on the inner ventral sur- 

 face of the buccal membrane, which serves for the attachment of the 

 spermatophores by the male. 



The pen is very thin, translucent, pale amber with the extreme 

 anterior end thin, abruptly pointed like a pen, the anterior shaft 

 long and narrow with a thin, lanceolate blade, with the edges curved 

 downward, the tip pointed, slightly thickened and curved a little 

 downward (fig. D.). 



Visceral anatomy: Verrill has given a masterly report of this 

 species (1882). 



References : Loligo pealeii Lesueur, Journ. Acad. Nat. Sci., Phila., 

 vol. II, p. 92, pi. 8, 1821. 



