348 
A. E. Verrill — North American Cephalopoda. 
full-grown. Body short, thick, swollen, with the mantle smooth. 
Ventral surface, in the middle, with a large, somewhat flattened, 
brown, heart-shaped or shield-shaped area, bordered with blue, and 
surrounded, except in front, by a silvery white band, having a pearly 
or opalescent luster. Eyes large, with roundish pupils. Fins large, 
thin, broadly rounded, in the living specimens nearly as long as the 
body; the posterior lobe reaches nearly to the end of the body; the 
anterior edge extends beyond the front of the mantle to the eye. 
The anterior edge of the mantle is emarginate beneath ; it recedes 
laterally to a great extent; above, it is broadly attached to the head. 
Sessile arms, largely webbed, short ; upper ones shortest ; third pair 
longest; suckers in two rows. Tentacular arms slender, tapering, 
extending back to the end of the body ; club not wider than the arm, 
with very minute suckers, in many rows. 
Upper surface of the body opalescent in some lights, thickly spot- 
ted with orange-brown, spots most numerous in the middle line and 
extending to the upper surface of the head ; some also occur on the 
outer surfaces of the arms ; anterior part of the head white ; fins, 
arms and extremity of body translucent bluish white ; upper surface 
of the eyes opalescent, with silvery blue and red tints; head, below 
the eyes, silvery white ; above the eyes, blue. 
The largest specimen, ( $ ) taken in 1879, (PL XXXI, fig. 5), when 
living had the head, above, in front of the eyes, whitish, with a few 
chromatophores ; back and the base of the fins thickly spotted with 
brown ; posterior part of the back with an emerald-green iridescence. 
Sides of the body, below the fins, and posterior end of the body, 
silvery white. A large shield-shaped ventral area of brown, with a 
bright blue iridescence, and bordered with a band of brilliant blue, 
occupies most of the lower surface. Fins, transparent whitish, except 
at base. Lower side of head, siphon and outer bases of the arms, 
light brown. Eyes blue above, green below. The fins are large, 
neai'ly as long as the body. 
Length of the original type-specimen ( $ ), to the base of the arms, 
14 mrn , in alcohol; of mantle, above, 8 mm ; breadth, 7 mm ; breadth 
across fins, 16 mm . The largest specimen, of 1879, is 31 ram (l - 25 inch) 
long from end of body to base of arms ; breadth of body, 25 mm (1 inch) ; 
length of arms, 19 mm (• 75 inch). 
The male (fig. 5) of this species differs from the female in having 
a group of three or four decidedly and abruptly larger suckers on the 
middle of the third pair of arms, (PI. LIV, fig. 4) ; the other suck- 
ers, along the middle portion of these arms, are also larger than on 
the other arms. 
