144 HAWAIIAN AND OTHER PACIFIC ECHINI. 



or less of a marginal fasciole, 1 and the absence of a subanal fasciole in spectabilis 

 seems to me a more serious matter than it does to Dr. Koehler. Unfortunately 

 the pedicellariae give little assistance since the two genera show no notable 

 differences. Pedicellariae in Palaeopneustes are abundant and varied. No 

 globiferous have been found but all of the other varieties occur. They 

 resemble in their main features those of Archaeopneustes. 



Key to the Species of Palaeopneustes. 



Primary spines numerous, not conspicuously longer and larger than the secondaries. 



Ambulacrum III not at all sunken; petaloid area of ambulacrum II only 6-10 mm. 



wide at distal end; labrum scarcely twice as long as wide; color dark violet . . cristatus. 

 Ambulacrum III depressed as a shallow furrow; petaloid area of II, 12-18 mm. 



wide; labrum thrice as long as wide; color red-brown with violet tinge . . . fragilis. 

 Primary spines relatively few, long and conspicuous; labrum more than thrice as long 

 as wide spectabilis. 



Palaeopneustes cristatus. 



A. Agassiz, 1873. Bull. M. C. Z., 3, p. 188. 



Plate 145, figs. 13-19. 



Of this fine West Indian spatangoid, only the pedicellariae need descrip- 

 tion. They are exceedingly abundant and show great diversity of form. The 

 ophicephalous, with valves (PI. 145, fig. 19) about .35 mm. long (including the 

 loop), have the blade triangular and wider than long. The triphyllous are 

 not very abundant; they have long necks and very small heads, the valves 

 (PI. 145, fig. 16) only .10 mm. long. The rostrate, with valves (PI. 145, figs. 

 18, 14) about .30-.50 mm. long, are fairly numerous; they are apparently only 

 broad tridentates modified to an extreme. There seem to be also at least four 

 forms of tridentate. The largest have valves (PI. 145, fig. 15) about a milli- 

 meter long, the blade narrow and somewhat involute but rapidly expanding 

 at tip. A second sort are similar but have shorter valves with wider blades. 

 In a third form, the valves (PI. 145, fig. 17) are about .30-.50 nun. long with 

 rather broad blades not at all abruptly enlarged at tip. Finally in the fourth 

 form, the valves (PI. 145, fig. 18) are very narrow, pointed, decidedly curved 



1 Mr. Agassis in the Bi.akk Kehini, ]>. oS, discusses the fasciole present in a specimen 16 nun. long, and 

 seemi uncertain whether it is a marginal fasciole or not. In my opinion, it is certainly a true marginal 

 fasciole, which though very tenuous is quite complete. Moreover in this same specimen there an 1 distinct 



fragments Of a peripetaloua fasciole. Hut neither in tins, nor in any other specimen is then" the least 

 indication of | subanal fasciole. 



