ECHINI >I1>KA. II. 



175 



the other has it en anneau appendicule par deux branches laterales , viz. the anal branches. Now 

 these anal fascioles are of very unconstant character, as repeatedly pointed out above — (they may 

 also occur in the true Br. lyrifera), and it is evidently impossible to ascribe to them any great 

 systematic importance. But then it follows that both Toxobrissus and Kleinia are synonyms only of 

 Brissopsis in its original meaning. If we have to subdivide the genus Brissopsis in its wide meaning, 

 it must then be as follows: 



Subgenus Brissopsis s. str. (Syn. Toxobrissus, Kleinia.) Type Br. elegans; Br. luzonica, atlantica, Old- 



hami, circoscinita. 

 Brissoma. Type Br. lyrifcra ; Br. alia, columbaris. 



Further Br. pacifica and elongata would make a separate subgenus, and perhaps one more 

 separate subgenus would have to be established for the new species mentioned above, in which the 

 first of the plates included within the subanal fasciole is the 7th as in pacijica and elongata. How- 

 ever, as pointed out above (p. 168), it seems to me the most natural thing to keep them all together 

 in one genus on account of the peculiar intermingling of all the more important characters. 



Lambert further includes under Brissopsis as subgenera: Plesiaster Pomel and Diplodetus 

 Sehliiter, which have the apex ethmophract. Though it is beyond doubt that the ethmolytic condi- 

 tion of the apex in the true Brissopsis has developed from an ethmophract condition, it seems to me 

 inappropriate to unite these different types in the same genus. I do not see, why we should be un- 

 able to keep in mind their close relation without uniting them into the same genus. The fact that 

 Hemiaster batnensis shows all transitional stages from an ethmophract to an ethmolytic condition can 

 scarcely justify uniting Plesiaster and Diplodetus with Brissopsis. (I am not aware that such trans- 

 itional forms are known in these genera.) 



Also the genus Schizaster is made the object of a careful analysis by Lambert. Sell, canali- 

 ferus is made the type of a distinct genus, with the character of the pores of the anterior ambulacrum 

 in double series. The rest of the old genus Schizaster is subdivided into the two (recent) subgenera: 

 Paraster, with 4 genital pores (P. gibbcrulus), and Brisaster with 2 genital pores (Br. fragilis, lacu- 

 nosus). — This subdivision again is the result of the lack of sufficient material of the recent forms. 

 If Lambert had had occasion to make a careful comparative study of the recent forms, he would 

 undoubtedly have seen that it is quite irrational to separate Sell, canalifcrus as a distinct genus from 

 lacunosus, orbignyanus etc. on account of the single feature of the double pores in the anterior ambu- 

 lacrum; these species otherwise agree so closely in all other features that it is evidently quite artificial 

 to separate them into different genera. Further, to unite lacunosus and fragilis in the same subgenus 

 can in no way be justifiable; I trust I have shown that beyond doubt (p. 120-123); probably Lambert 

 has not seen these species himself, otherwise he could scarcely have come to this conclusion. (The fact 

 alone that he characterises the subgenus Brisaster with type species : Br. fragilis as having two 

 genital pores seems to show this.) 



I have above repeatedly alluded to the opinion of Lambert, that the names Spatangus and 

 Schizaster are not rightly used in the way generally accepted. Here he finally makes the change: 

 Schizaster canalifcrus is made the type of the genus Spatangus (the former genus Spatangus is called 



