318 HAWAIIAN AND OTHER PACIFIC ECHINI. 



The difference in the descriptions of the color of the spines, is probably of degree 

 rather than of kind, but in the type of Temnotrema the spines are now missing 

 or broken, so that it is impossible to speak positively on this point. Since 

 sculpta (= Mortensen's variegatus) seems to be undoubtedly congeneric with 

 Agassiz's bothryoides, it is clear that the generic name Temnotrema must replace 

 Pleurechinus for this group of Temnopleuridae, and sculpta becomes the type in 

 place of bothryoides. 



As the genus has been so recently (1904) and so fully revised by ^Mortensen, 

 there is no need for a discussion of the species. Only four of the seven species 

 he tabulates are at hand, but there appears to be no reason for questioning any 

 of the others and his list with the addition of the new species found by the 

 "Albatross" among the Hawaiian Islands, may be accepted. All of the species 

 are found in the Indo-Pacific region, especially among the East Indian Islands; 

 perhaps sculpta is confined to Japanese and Formosan waters, as hawaiiensis 

 appears to be to the Hawaiian region. A specimen of Doderleini in the M. C. Z. 

 collection from Fiji may be recorded here; this however is not sui'prismg as it 

 was already known from Samoa. 



As Mortensen has made considerable use of the pedicellariae in his table, 

 and as their characters seem of very little importance and not altogether reliable, 

 the following table, showing additional characters by which the eight species 

 may be distinguished, is offered. 



Buccal plates 10; anal plates not very numerous, a suranal usually evident. 



Pits large, the distance between the two of same horizontal interambulacral suture 



less than the length of one. 



Anus central or nearly so; periproct without a conspicuous suranal; test high 



(v. d. may equal .75 h. d.) uniformly dark; primary spines light with 2-4 red 



hands; valves of globifcrous pedicellariae with a lateral tooth on each side 



near t ij) holhryoides. 



Anus more or less oxcontric; suranal distinct; test not uniformly dark; viJvcs 



of globifcrous podicollariic witliout lateral teeth. 



Test not very high, v. d. = .5O-.60 h. d.; suranal plate very large, covering 



lialf or more of periproct. 



Spines, at least secondaries, thorny, not swollen at tip; poriferous area 



J to i as wide as interporiferous; coronal plates conspicuou.sly 



sculptured around primary tubercles scilltr. 



Spines smooth; primaries often swollen at tip; poriferous area J to J 

 as wide as interi)oriferous; con)nal plates little sculptunxl an>und 



l)rimary tul)ercles siamensis 



Test rather high, v. d. = 60-.70 h. d.; .suranal plate moderate not covering 

 half the periproct. 

 Genital plates marked by a transverse line which appears to divide the 

 distal from tlio i)n)\imal part; tubercles on coronal plates in 

 horizontal rows; no green in coloration maculate. 



