﻿UPlllOGLYrUA U015USTA. 45 



Ophioglypha robusta Lyman. 



Ophinh'pis rohii^Ui Aykks. Pnicci'd. liusfiin Scir. Xat. Illst., IV. p. 1,'!4. 1851. 

 Ophiura fanciciUata FoitUEs. A|)peuilix to Sutliurlanirs Jum-nal of a Journey. 

 Opiuura squnmosa l.VTKEti. Vidensk. JMcddelelser. Nov., 185-1. 

 Ophiura squamosa LiJTKEN. Addit. ad Hist. Oph., p. 4G. 



Special Marks. — Mouth-shields nearly heart^shape, broader than 

 long ; arms very finely tapering, as long as three or four times the 

 diameter of the disk. 



Description of a Specimen. — Diameter of disk, 7.7"""' ; from outer 

 side of mouth-shield to outer corner of opposite mouth-slit, 3. 8""°- ; 

 width of arm without sjiines, 1.2°"° ; length of arm, 32™"' ; distance 

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

 that between outer corners of mouth-slits, 2 : 1.8. Mouth-papillfe, seven 

 or eight to each angle of mouth ; outermost one broadest, thin, flat, 

 squarish, with a bevelled cutting edge ; three innermost ones forming a 

 row at the inner mouth-angle ; nearly equal, stout, rounded, pointed ; 

 all pointing to centre of mouth. Teeth, five or six, equal, crowded, 

 sharp, flat, with curved sides, like a spear-head. Mouth-shields broad 

 heart-shape, strongly curved without, within pointed, broader than long, 

 length to breadth, 1.2 : 1.5. Side mouth-shields occujiying inner sides 

 of mouth-shields, meeting withua ; long, narrow, but little broader with- 

 out than within. Under arm-plates broader than long, bounded without 

 by a slightly re-entering curve ; on the lateral side, by a very short, 

 nearly straight hne ; and within by two re-entering curves, converging 

 in a peak ; length to breadth (sixth plate), .5 : .7. First plate quite 

 different from the others, being nearly oval ; length to breadth, .5 : .8 ; 

 second plate proportionately longer than those beyond ; at tip of arm, 

 plates heart-shape, and extremely minute, compared with size of joint. 

 Side arm-plates strongly developed, meeting below, and there forming 

 a line of juncture, which, at base of arm, is about half as long as an 

 under arm-plate ; not meeting above till nearly half-way out on arm. 

 Upper arm-plates diamond-shape, with outer angle rounded, and inner 

 angle truncated, sometimes approaching a hexagonal shape ; length to 

 breadth (fifth plate), .7 : .9 ; first two or three plates rudimentary and 

 irregular, of these usually two are embraced in the notch of the disk ; 

 near end of ann, plate heartrshape, Avith a sharp point inward. Disk 

 scales irregular in shape and size, none very large, very little swelled ; 

 primary plates not prominent ; near margin of disk about 4 to a square 

 7nm. ; the largest scales have a diameter of .8™"' ; below, scales veiy 

 similar, but not quite so large. Radial shields inconspicuous, irregularly 

 ^ triangular, about as long as broad, somewhat overlapped by neighboring 



