NUDECHINUS STICTUS. 279 



only .10 mm. in length, the width of the blade being a trifle less. No calcareous 

 spicules were found. 



The color of the three specimens displays some diversity. The smallest 

 has a light gray test, with a few scattered greenish blotches abactinally; the 

 spines are white, dark brown at the very base. The type is greenish yellow 

 with the primary spines whitish, dull green at the very base. The large speci- 

 men is yellowish green with the primaries whitish, deep green at the very base. 



The type and the small specimen are labelled " de Suez, Vaillant. Psammechi- 

 nus de Liitken." They were obtained in Paris in 1869 by Mr. Agassiz, but were 

 never identified by him. The large specimen was purchased in Hamburg in 

 1870 by Mr. Agassiz and bears the label "New Zealand." It is probable that 

 one, if not both, of these locality labels is erroneous and as the latter appears 

 to be the less reliable of the two, the Indian and East African coasts will 

 possibly prove to be the home of this species. It seems to be nearly related 

 to inconspicuus Mortensen but is easily distinguished by the genital plates, 

 the tuberculation and the coloration. The pedicellarise are remarkably similar 

 to those of inconspicuus. 



Nudechinus stictus, 1 sp. nov. 

 Plates 93, fig. 1; 97, figs. 1-3. 



The type and only available specimen (PI. 97, fig. 1) of this new form is 

 undoubtedly very young, although the pores in the genital plates are perfectly 

 distinct. It measures 6 mm. in diameter and rather more than 3 mm. in height; 

 the actinostome is more than 3 mm. across and the abactinal system, more than 

 1 mm. The primary spines are about 1.3 mm. long. There are 9 or 10 inter- 

 ambulacral, and 10 or 11 ambulacral plates in each column. Aside from the 

 primary tubercles, only a few small scattered secondaries or miliaries have been 

 observed; on the interambulacral plates at the ambitus an imperfect circle 

 around the primary tubercle is formed by these secondaries. The genital plates 

 (PL 97, fig. 3) are nearly of a size and each carries a single tubercle or none; the 

 pore is in the distal angle. The oculars are relatively large, all exsert, though I 

 is nearly insert; each with a single tubercle but apparently with no pore. The 

 periproct is rather larger than a genital plate and is covered by four plates of 

 which the suranal is largest. The poriferous areas are narrow, with the pores 



s = spotted, dappled. 



