ADDENDA. 383 



culatus" and " Sahnacopsis pulchellimus" are synonyms of Mespilia globulus, 

 and that " Echinostrephus pentagonus" is a synonym of Echinostrephus molaris. 

 Of the other six species, three are clypeastroids and will be discussed in part 5 

 of the present work. The three remaining species are cidarids and a few com- 

 ments on them may be given here. 



Cidaris (Stereocidaris) tenuispmus Yoshiwara. Examination of the type and 

 a cotype of this species leaves no doubt that the conclusion reached in 1907 that 

 it is identical with Doderlein's Dorocidaris japonica, is correct. For a full 

 discussion of the matter, see A. Agassiz and Clark, 1907, Bull. M. C. Z., LI, p. 

 112-114. 



Cidaris (Stereocidaris) microtuherculatus Yoshiwara. Examination of the 

 type-specimen confirms the validity of this species, which has already been 

 diagnosed and figured (1907, Bull. M. C. Z., LI, p. 220, pis. 1 and 2). 



Cidaris (Porocidaris) misakiensis Yoshiwara. The most striking feature of 

 the beautiful specimen on which this species is based is found in the primary 

 spines, which are more like those of some species of Cidaris (rugosa H. L. C. for 

 example) than they are like those of the other species of Porocidaris. They are 

 thickest not far from the base and then taper steadily to a blunt point. They 

 are longitudinally striated with about 28 series of minute, sharp prickles, much 

 as in P. Sharreri. The longest spines are 95-100 mm. in length and 5 mm. in 

 diameter, 10-12 mm. above the base. The primaries are pure white, while the 

 secondaries, pedicellarise, and test are white with a tinge of yellow. Yoshiwara 

 says the test, especially abactinally, and the collar of the primaries is ''deep 

 brown" and the secondary spines "brownish." Evidently the specimen has 

 become completely bleached in alcohol. The abactinal system is .40 h. d. in 

 diameter. The pedicellariae are similar to those of P. variabilis and some of the 

 large ones have valves 5 mm. long. — There is no doubt that misakiensis is quite 

 distinct from elegans and it appears to be equally different from variabilis, but 

 it is very close to Sharreri and so far as our material shows, the form of the pri- 

 mary spines is the only difference worthy of mention. The specimen, described 

 and figured by deMeijere ("Siboga" Ech., p. 27, PI. 2, figs. 15, 16) as misakiensis, 

 does not agree well with the type, and it is doubtful if it is the same species. 

 It may be, as de Meijere suggests, only a form of elegans or it may possibly be 

 variabilis. The specific differences in the genus are very intangible and much 

 more material is necessary, from both the East and West Indies, before the 

 species already described can be satisfactorily known. 



