350 A. E. Verrill — North Auterican Cephalopods. 



which forms a loose border posteriorly ; the front edge of the mantle 

 extends forward dorsally into a prominent angle, bnt recedes very 

 much ventrally. Fins very large and broad ; their anterior insertions 

 being but little back of the antero-lateral edge of the mantle, and 

 their posterior insertions close to the end of the body ; the free bor- 

 ders of the fins are thin and undulated, extending forward anteriorly 

 beyond the edge of the mantle, while the length, from base to outer 

 edge, is about equal to the breadth of the back between the bases of 

 the fins. 



Head very large and broad, the width exceeding that of the body. 

 Eyes very large and prominent ; lower eyelids well developed, but 

 not much thickened. Tentacles remarkably long and slender, in ex- 

 tension about twice as long as the head and body together. The 

 tentacular club is somewhat tliicker than the rest of the arm, rather 

 long, narrow-lanceolate, tapering to the tip, and covered with nu- 

 merous minute, globular suckers, arranged in many rows (PI. XLVI, 

 fig. 6, b-d). Sessile arms of moderate length, rounded, very slender 

 at tip ; the 1st, 2d and 3d pairs are successively longer, while the 4th 

 or ventral pair is about equal to the first. Suckers, (PI. XLVI, fig. 

 6, a), rather small, arranged in two rows on all the arms. On all the 

 arms the suckers are similar but are a little larger on the 3d pair. 

 They are nearly globular, with a rather wide aperture, which is sur- 

 rounded by a border covered with numerous small scales, arranged 

 in many rows ; the scales of the marginal series are larger and project as 

 fine denticles around the aperture. Color purplish brown, with rather 

 large chocolate-brown chromatophores ; outer portion of fins pale, 

 thin and translucent ; edges of mantle, siphon, under side of head 

 and arms, and greater part of tentacular arms whitish, with only 

 minute chromatophores. 



Measurements of Rossia megaptera. 



Inches. Millimeters. 

 Length, end of body to dorsal edge of mantle, exclusive of mem- 

 brane, --_ 1-25 32 



Length, end of body to ventral edge of mantle, . _ -95 24 



Length, end of body to base of dorsal arms, -.-_ 2-25 57 



Length, end of body to tip of dorsal arms, 3-40 86 



Length, end of body to tip of 2d pair, 3 75 95 



Length, end of body to tip of 3d pair, 4-08 1 03 



Length, end of body to tip of 4th pair, 3-75 95 



Length, end of body to tentacular arms, 7-45 188 



Breadth of body and fins together, .. .. 2-50 63 



Breadth of body between bases of fins, -85 22 



Breadth of body beneatli fins, exclusive of membrane, 111) 28 



