SALENOCIDARIS CRASSISPINA. 61 



This species was taken by the " Albatross" at the following stations: 



Station 4060. Off Alia Point Light, N. E. coast of Hawaii, Hawaiian 

 Islands. Bott. temp. 30.5°. 759-913 fathoms. Fne. gy. vol. s. for. r. 



Station 4125. Off Kahuku Point, Oahu, H. I. Bott. temp. 36.4°. 963- 

 1124 fathoms. Br. m. for. r. 



Station 4181. Off Hanauiaulu, Kauai, H. I. Bott. temp, 38.1". 671- 

 811 fathoms. Manp;. s. fflob. 



Station 5084. Off Omai Saki Light, Hondo, Japan. Bott. temp. 36.8°. 

 918 fathoms. Gn. m. fine. s. glob. 



Bathymetrical range, 671-1124 fathoms. Extremes of temperature, 

 38.1°-36.4°. Six specimens. 



Salenocidaris crassispina A. Ag. and CI. 



Salenia crassispina A. Agassiz and Clark, 1907. Bull. M. C. Z., L, p. 234, 

 Plates 45, fig. 9 ; 52, figs. 1-7. 



A single small specimen of this species (PL 52, figs. 1-2) was collected off 

 the West coast of Hawaii in comparatively shallow water, 147-198 fathoms. 

 It measures 4.8 mm. in diameter and 3 mm. in height, and the actinostome is 

 1,7 mm. in diameter. It is undoubtedly an immature specimen. 



It has five-six or six-six interambulacral plates, with two large secondary 

 tubercles at the median suture and one or two smaller tubercles at the line 

 of junction (PI. 52, fig. J^) between the ambulacral and interambulacral 

 systems. Three or four of the primary interambulacral tubercles, with huge 

 mammary bosses, are much larger than the others and carry remarkably 

 stout radioles (PI. 52, figs. 5-7), which, though distinctly distantly verticillate, 

 yet are quite smooth (PI. 52, fig. 6) save for a little serration near the slightly 

 curved tip of the spine (PI. 52, fig. 7). 



The diameter of the radioles is frequently equal to, or even larger than, 

 that of the milled I'ing, and the longest one is only 19 mm. There are 

 nine-nine or nine-ten ambulacral plates, their tubercles occupying the whole 

 median part of the plates. The ambulacral pores are on the lower angle 

 of the plates, and on the upper plates can barely be distinguished (PI. 52, 

 fig. 3), the tubercles occupying nearly the whole of these upper plates. The 

 Hemicidaris-like development of the actinal tubercles is very marked (PI. 52, 

 figs. 1, 3). The ambulacral miliaries are short. On the actinal side of the 

 test there are a few short, pointed, flat serrated radioles. 



