﻿44 



OPHIOGLYPHA SARSII. 



mouth-shield, and one on the other side ; the rest of the pores have but 

 one scale. Upper side of the disk almost completely covered by pri- 

 mary plates and radial shields, which are rounded and much swollen ; 

 of the primary plates, there is a rosette of six in the centre, and three 

 in each interbrachial space. A larger specimen had a disk of 7°"°', and 

 arms 24""- ; and another had the disk 10.5°"", arms 42"'"-. The mouth- 

 shields vary somewhat in proportionate length ; those of the young 

 have a deeper depression where they touch the mner end of the genital 

 slit. The adult have the disk-scales flatter, and the primary plates and 

 radial shields more conspicuous, by reason of the many small scales 

 between them. Dr. Liitken mentions a variety (0. coriacea Ltk.) which 

 has only one tentacle-scale, and the disk-scales very small ; and another 

 (perhaps a variety) which has no papillae on the incision of the disk, 

 arm-spmes only half as long as in 0. Sarsii, and a hairy or felted cover- 

 ing over the surface (0. ardlca Ltk.). The color of the living animal 

 is a mixture of green, yellow, and gray, with sometimes light bands on 

 the arm (Barrett). 



0. Sarsii has been found in Massachusetts Bay, and at the Grand 

 Manan (Stimpson) ; along the whole coast of Greenland (HolboU, Bar- 

 rett, &c.) ; at Spitzbergen, and on the coast of Norway (Sars). It is 

 distinguished from O. robusta by the different scaling of the disk ; from 

 0. tcxhirata, by wanting pores on the under side of the inner arm-joints ; 

 from 0. carnea and O. albida b}- longer arm-spmes ; and from 0. Liit- 

 kenii, by the double row of notch papdla?, and by their greater sharp- 

 ness. 



LIST OF SPECIMENS. 



1022 

 1025 



1040 

 1095 



Ifuseum of Comparative Zoo^orjy. 

 Grand ^lanan Island 

 and Eastport, jVIe. 

 Eastpoit, Mu. 

 Greenland. 



Greenland. 

 Trenton, Me. 

 JIassacliusetts Bav. 



Smithsonian Institution. 



Grand ^Nlanan Island, 

 ^lassachusetts Bay. 

 Coast of jMe. and Mass. 



Prof. Asassiz. 

 J. E. ilills. 

 Univei-sity Museum, 



Copenlia<ren. 

 Prof. Sai-s, 1852. 

 A..E. Verrill. 



University Museum, 



Copenlia^ren. 

 University Museum, 



Copenhajren. 

 Wm. Stimpson. 

 Wm. Stimpson. 

 Wm. Stimpson. 



