SCHIZASTER LATIFRONS. 



205 



openings. The two anterior genital plates, Fig. 296, are ankylosed and 

 carry the madreporite. In a large specimen (PI. 98, figs. ./, /;) there are 

 three genital pores. The right anterior genital pore is wanting, Fig. 29o. 

 The left anterior and the two posterior pores are large. The ri«^ht anterior 

 and posterior genital plates are ankylosed (PI. 98, figs. 3, G). 



5 



17 mm 



Fig. 295. Nacospatangus gracilis. 



li.5 mm. 



Fig. 290. NACosPATAXor.s gracilis. 



In Agassizia there are fo\n' genital pores. Three genital plates are faintly 

 indicated in young specimens of 5 mm. (PI. 108, figs. •?, 5). In larger speci- 

 mens (16 mm.) there is a faint longitudinal suture to be seen on the interior 

 of the test (PI. 108, fig. 9). On the whole the abactinal system of the two 

 genera are very similar. 



Nacospatangus gracilis was dredged by the ''Hassler" in 65 fathoms off 

 Juan Fernandez. 



ScHizASTER Agass. 

 Schizaster latifrons A. Ag. 



Schizaster latifrons A. Ag., Bull. M. C. Z. 1898, XXXII, No. 5, p. 81, non PI. XT, figs. 2, 3. 



Plate 102, figs. l-J,. 



At Station 3431, in 995 fathoms, were collected specimens of a species of 

 Schizaster remarkable for the great development of the anterior extremity, 

 the breadth of the odd anterior ambulacrum (PI. 102, fig. j), and the 

 short posterior pair of lateral ambulacra. The subaual fasciole is delicate, 

 does not join the peripetalous fiisciole (PI. 102, fig. 4). The actinal plastron 

 is well marked by the two large plates which occupy nearly the whole 

 length of the odd posterior actinal interambulacrum. 



