﻿OPIIIONEREIS rORRECTA. 



147 



LIST OF SPECIMENS. 



Catarojjue Original Number 



Whence obtained. 



Museum of Comparative Zoology. 

 31 I 11C4 I 1 I Cape St. Lucas, Cal. | | J. Xantus. | Alcoholic 



Smillisonian IiistUution. 

 11C4 I . . I 5 I Cape St. Lucas, Cal. I I J. Xantus. I Alcoholic 



Ophionereis porrecta Lyman. (Figs. 14, 15.) 



Ophionereis pnirecta Lyman. Proceed. Boston Soc. Nat. Hist., VII. p. 2G0. 18G0. 



SjJecicd Harks. — Dull reddish-brown. Arms, in adult specimens, 

 nine times as long as the diameter of the disk. Arm-spines short. 



Description of a Specimen. — Diameter of disk, 12"""- ; from outer 

 side of mouth-shield to outer corner of opposite mouth-sht, 4.5°'°' ; 

 width of arm without spines, 2.5'""'-; length of arm, 113""-; distance 

 from outer side of mouth-shield to inner points of mouth-papilla3, to 

 that between outer corners of mouth-slits, 2 : 2.2. Mouth-papilla? ten, 

 short, stout, the outermost but one broadest. Teeth four or five, stout, 

 squarish, rather long, a little tapering, lowest one shortest. Mouth- 

 shields oval ; length to breadth, 1.6 : 1. Side mouth-shields very small, 

 triangular, sometimes almost obUterated. Under arm- 

 plates squarish, broader without than within ; outer side 

 curved, inner side nearly straight, lateral sides re-enter- 

 ingly curved; length to breadth (twentieth plate), 1:1.2; 

 (fortieth plate), 1 : 1.4. The first plate is wedge-shaped, 

 with a curved outer side. Upper arm-plates varying in 

 proportionate breadth according to the width of the arm, 

 usually broader than long ; inner side much longer than 

 outer one ; outer and lateral sides sometimes distinguished, 

 and sometimes confounded in a common curve ; length 

 to breadth (sixth plate), .8 : 1.5 ; (thirty-fifth plate), 1 : 1.6. Scales of 

 disk rather stouter than usual in the genus ; about 80 to a square mm. 

 Radial shields 1.2"""- long. Scales on edge of disk larger than the rest. 

 Papillag along edges of genital slits stout and prominent. Arm-spines 

 short, rounded, tapering ; lengths to that of under arm-plate (twenty- 



