REPORT ON THE OPHIUROIDEA. 241 



(Type specimen from Station 235.) Diameter of disk 3-5 mm. Width of arm next 

 disk 1'2 mm. Three short, narrow, slightly flattened, peg-like teeth, carried on a 

 thick, lumpy jaw plate, which also bears two long flat narrow, spatula-like tooth papillte. 

 On either side of the mouth angle are two radiating rows, each of about six long, 

 flattened papillse, which are imbricated and point downward and outward, so that the 

 entire mouth angle is hidden by them ; the inner ones are narrow and spatula-like, 

 but outwards they grow rapidly larger, so that the outermost are wide paddle-shaped, or 

 even fan shaped, their length to extreme breadth being 7 : '5. Mouth shields shaped 

 like a long, sharp, narrow lance head. Side mouth shields three sided, delicate, separated 

 as by a wedge by the mouth shield, which extends inward considerably beyond them. 

 Within, and indistinctly separated from the side mouth shields project the long jaws. 

 These parts are all hidden, and can be seen only by cutting away the mouth papillae. 

 Under arm plates small, with re-enteringly curved lateral sides, wider without, where 

 they are a little swollen, than within, separated by the side arm plates, which meet 

 narrowly both above and below, and are highest and most flaring at their outer edge. 

 Upper arm plates minute (sometimes apparently wanting), twice as long as broad, and 

 appearing like little swellings just outside the juncture of the side arm plates. The 

 larger part of upper surfixce of arm is thus left uncovered, so that the arm bones and 

 their muscular bundles may be seen. Disk (as usual in the genus) distorted and pushed 

 upward, covered uniformly with minute, thin, translucent, flat scales, without spines ; 

 there are about 13 in the length of 1 mm. Ten arm spines, of which the three highest 

 are equal, slender, narrow and tapering, and as long as any ; the next two are of about 

 the same length, but broad and flat, with rounded ends ; the next three similar, but 

 shorter ; the two lowest spatula like, with ends cut square off", and carried, not on the 

 side arm plate, but widely spaced on the outer part of the under arm plate ; lengths to 

 that of an arm joint, "5, '5, '5, '5, "5, '4, "4, '3, '3, "3 : "5. One flat, short, wide tentacle 

 scale, bi"oader without than within, and, like many of the arm spines and mouth papillse 

 microscopically striated. Colour in alcohol, disk, grey ; arms, straw. 



Station 235.— June 4, 1875 ; lat. 34° 7' N., long. 138° 0' E. ; 565 fathoms; mud. 



Ophiomyces grandis (PI. XIX. figs. 13-15). 



Ophiomi/o's grandis, Lym., Bull. Mus. Comp. Zool., vol. vi., part 2, p. 46, pi. xiv. figs. 383-385, 

 1879. 



Eleven sharp, flat arm spines, set along the whole upper and side edge of the ^jlate, 

 and growing longer from above down to the ninth. Basal under arm plates, large and 

 squarish, and bearing three long spatula-like tentacle scales. 



(Type specimen from ofi" Tristan d'Acunha.) Diameter of disk Q'b mm. Length of 

 arm about 25 mm. Width of arm near disk 2 "2 mm. Four or five broad, flat teeth 

 with a curved, cutting edge ; the lowest one being much the narrowest. Below these. 



