294 NEW STARFISHES AND OPHIURANS—VEERILL. vol.xvii. 



and rather widely separated by a group consisting of two large me- 

 dian and several smaller scales on each side; the radial shields are 

 irregular, polygonal, or somewhat triangular in form, about as long as 

 broad, with the outer end subtruncate or broadly rounded, and the 

 inner end bluntly pointed and strongly divergent. The interbrachial 

 areas beneath are covered with thick imbricated scales, similar to those 

 of the back, and about 15 mm. in breadth. 



The mouth shields are pretty regularly shield-shaped, the breadth 

 about equal to the length, the outer margin broadly rounded or sub- 

 truncate, the lateral margins nearly straight, and the inner margins 

 convergent to a point and forming sometimes a right angle, but usually 

 an obtuse angle; side mouth -plates narrow, with nearly straight, some- 

 what divergent edges, with the widest end toward the jaw. Mouth- 

 papillse numerous and regular, acute conical, seven or eight in number, 

 increasing in length as they approach the end of the jaw. 



The genital slits are very long, extending from the mouth-shields to 

 near the underside of the arms; they are bordered externally by a row 

 of short, thin, wedge-shaped, or squarish papillie, which stand close 

 together in a regular row; those nearest the mouth shields are much 

 the smallest and shortest, and are often nearly square, but in many 

 cases are twice as broad as high ; their height usually increases distally 

 to the outer end of the slit, where they are sometimes fiat, nearly 

 square, and as long as the arm-spines. In many cases they are more 

 or less soldered together into a continuous series, and in tlie larger 

 specimen they are often partially wanting. 



Innermost tentacle-pore very large, elongated, with about eight regu- 

 lar, flattened, obtuse papillae on each side; on the next two pairs of 

 tentacle-pores the jjapillfe are smaller, but nearly as numerous; on 

 the fourth pair there are about four on each side ; and on two or three 

 succeeding pairs there are two; beyond that, only a single papilliform 

 tentacle scale. At the base of the arms there are three small, papilliform 

 arm spines, nearly equal in size, the upper one separated from the two 

 lower ones, which are close together; sometimes three spines appear 

 in the lower group. They are about one-third the length of the side 

 arm-plates ; the upper one is often a little larger than the others. 



The first under arm-plate is small and pentagonal; the second and 

 third are considerably larger, pentagonal, about as long as broad; the 

 third to the sixth separate the side arm plates and are transversely 

 elliptical, with an inner angle, broader than long; beyond this the 

 plates gradually become shorter and relatively broader, and the side 

 arm-plates come more and more broadly in contact. The upper arm- 

 plates are strongly convex and prominent, but not much thickened; 

 the three at the base of the arms are short and broad; the fourth is 

 hexagonal, broader than long; beyond this the form becomes regularly 

 hexagonal and the length becomes greater than the breadth, and dis- 



