A. E. Verrill — North American Oephalopods. 



349 



This species is an exceedingly beautiful one, when living, owing to 

 the elegance and brilliancy of its colors and the gracefulness of its 

 movements. In swiminino- it moves its fins in a manner analogous to 

 the motion of the wings of a butterfly. This fact, and its bright 

 colors, suggested the English name that I have applied to it. 



Three specimens, two very young, were taken by the writer and 

 party, of the U. S. Fish Com., in the trawl-net, 30 miles east from 

 Cape Ann, Mass., in 110 fathoms, August, 1878. One larger male 

 was taken by us off Cape Cod in 122 fathoms, with the bottom tem- 

 perature 41° F., August, J 879. The largest specimen seen was a 

 male, taken in the same region, Sept. 10, 1879, in 94 fathoms. It was 

 associated with Octopus Bairdii and Rossia sitblevis. 



ROSSIA Owen. 

 Rossia Owen, Trans. Zool. See. London, 1828 (t. Gray); Owen, in J. Ross, Second 

 Arctic Voyage, Appendix, p. xcii, pi. 100. 1835. 

 D'Orbigny, Cephal. Acetab., p. 242. 

 Gray, Catal. Moll. Brit. Mus., i, p. 88, 1849. 



Mantle-edge free from the head dorsally, adhering by a longitudi- 

 nal, ovate or horse-shoe-shaped connective cartilage, having a median 

 and two lateral grooves, fitting into corresponding grooves on the 

 cartilage of the mantle ; two lateral, oblong, ridge-like cartilages, one 

 on each side, also fit into ovate cartilage pits on the base of the 

 siphon. No olfactory crests. Pupils oblong or crescent-shaped, lon- 

 gitudinal. A false eye-lid below the eye. A pore in front of each 

 eye, and one, on each side, between the bases of the third and fourth 

 pairs of arms. Tentacular arms more or less retractile into large 

 cavities at their bases, extending back beneath the eyes ; club well 

 developed, with numerous, nearly equal suckers, forming eight or 

 more rows ; rims not toothed ; borders scaled. Buccal membrane 

 with only six lobes, without suckers. The males differ from the 

 females in having larger suckeis on the middle of the lateral arms. 



Rossia megaptera, sp. nov. 



Plate XXXVIII, figure 1. Plate XLVT, figure 6. 

 Body short, broad, depressed, covered with a soft, flabby integument, 



