40 NATURAL HISTORY BULLETIN. 



E. E. — -One or two tentacle-scales. 



p. — Ophiolimna. gen. nov. (See p. 44). Arm-spines sev- 

 en or eight, nearly smooth, placed obliquely on the distal part 

 of the plates, not strongly divaricate. Jaws more or less 

 granulated. Disk-scales and radial shields concealed, bear- 

 ing granules and spines. 



* O. Bairdii (Lym.) Upper arm-plates separated. Rows 

 of spines approximate dorsally. Tentacle-scale single. 



O. mitra Lym. Upper arm-plates joined. Rows of 

 spines wide apart dorsally. Two flat tentacle-scales. 



p. p. — Ophiopristis. gen. nov. (see p.. 44). Arm-spines 

 serrulate, not obliquely placed. Strongly divaricate. Dorsal 

 arm-plates separated. Tooth-papillae usually three. 



q. — Spines partly flattened, serrulate on the edges. A 

 row or cluster of several distal oral papillae at the large, oral 

 tentacle-pore. Two tentacle-scales on the basal joints. 



O. hirsuta (Lym.) 



O. ensifera Ver. sp. nov. 



O. cervicornis (Lym.) 



q. q. — Ophiotreta Ver., subgen. nov. Only one or two, 

 rarely three, oral tentacle papillae, which are flat. Two to 

 four or more tooth-papillae. Arm-spines terete, or only a lit- 

 tle flattened, slender, serrulate or nearly smooth. 



O. lineolata (Lym.) 

 O. sertata (Lym.) 



D. D. — Ophiothamims Lym. Adoral shields large, wedge- 

 shaped, with the broad distal end separating the narrow ovate 

 oral shield from the side arm-plate. Disk-scales exposed. 

 Radial shields more or less naked, close together. 



