162 Bulletin Vanderbilt Marine Museum, Vol. VII 



Technical description: The disk is pentagonal, with the 

 circumferal margin of each interbrachial area concave. The disk 

 diameter is 9 millimeters. The abactinal and interradial areas 

 of the actinal surface are similarly encased in a tough integument 

 which has numerous coarse, rounded or rough granules embedded 

 therein. The genital slits are long. The abactinal surface of the 

 disk is heavily pencilled with meandrine brown lines which de- 

 fine a pattern of irregular lozenge-shape design. The central 

 mouth shield is deeper than wide, heart-shape, with the rounded 

 apex directed inward. The side mouth shields are rather wide, 

 triangular, with the tapered apices almost, but not quite, meeting 

 within. Mouth papillae four on each side of the jaw-angle, the 

 outer of which is tapering and pointed, the second is wider than 

 long and rounded, the third and fourth, or innermost, mouth 

 papillae are squarish. There is a total of fifteen nearly equal, 

 bead-like tooth papillae. There are four teeth, of which the upper 

 one is the largest ; all are stout, thick, with rounded corners and 

 blunt cutting edge. 



The arms are encased in a tough integument, similar to that 

 of the disk with that of the dorsal surface regularly granulosa; 

 the arm plates show through this skin. The ventral arm plate is 

 longer than wide, with the distal margin regularly convex, the 

 proximal margin very narrow, and the lateral margins oblique 

 proximally, thence concave for their greater distance, beside the 

 tentacle scale. There is but one tentacle scale, which is very 

 widely oval, flat. 



The side arm plates are wide, with the distal margin convex. 

 Each plate supports two or three spines, the dorsal of which is 

 the longest, this spine being one and a half to twice as long as the 

 ventral spine; the median spine is similar to the ventral one. 

 These spines are stout proximally, tapered distally, with conical 

 blunt, spinose tips. 



The dorsal arm plates are hexagonal, with the proximal-median 

 and distal-median margins shorter than any of the others which 

 are approximately equal. 



There is a dark brown stripe on the upper arm. The arm 

 spines are each ringed transversely with three to five dark brown 

 bands alternating with cream. 



Herklots' early figure of the type in colour, and H. L. Clark's 



