SHALLOW- WATER STARFISHES 287 



onaster (restr.), and Tosia (restr.) — into one large genus, for they 

 are closely related. In that case the name Goniaster should be 

 applied to the entire group, under which the other two names might 

 be retained for subgenera or sections. Goniaster is certainly the 

 earliest of these names, under the binomial system. 



The restriction of Goniaster to a species not mentioned by Agassiz 

 {obtusangnlus Lam.), as has been done by Perrier and by Sladen, 

 is entirely contrary to the rules of nomenclature, and quite unjustifi- 

 able. Therefore the latter was made the type of a genus {Pseudore- 

 aster) by me in 1899. 



Astrogonium of Miiller and Troschel, 1842, should properly have 

 been dropped from the system long ago. It was a very heterogeneous 

 group, composed (as the authors themselves stated), of several of 

 Gray's genera recombined. This unnatural combination has been 

 rejected by many subsequent writers. It is a synonym of Gray's 

 genera. 



Astrogonium was nearly equivalent to the typical Goniasterinae, 

 collectively. 



Hippasteria. The type of the latter was the first-named species 

 of Astrogonium. 



Gray, 1866, endeavored to restrict Astrogonium to a minor group, 

 but his first and most typical species (granularis) is a Tosia, accord- 

 ing to Gray's definition of the latter. Others belong to very different 

 genera. 



Sladen restricted it to the group named Pentagonaster by Gray 

 and Stephanaster by Ayres, which is contrary to the generally 

 accepted rules of priority. Other attempts to restore it have been 

 equally unfortunate. Perrier formerly used it for a section of 

 Pentagonaster. 



Goniodiscus Miiller and Troschel embraced several diverse genera 

 of Gray's system (as stated by them), such as Paulia, Anthenea, 

 Randasia, Nectria, Hosea. Their first species (pentagonulus) , pre- 

 sumably intended as the type, was also the type of Gray's Anthenea. 

 Two of their species belong to Tosia Gray. 



Perrier, and also Sladen, have restricted it to several species 

 referred to Hosea by Gray in 1847 and 1866. The latter genus was, 

 however, founded by Gray in 1840, with a single species (H. Haves- 

 cens Gray) as the type. Perrier, who has studied this type, states 

 that it is a true Anthenea. If this be so, Hosea becomes a synonym 

 of the latter. 



