A. E. Verrill — Revision Genera and Species of Starfishes. 157 



been able to examine are to be depended 'upon. I have not had a 

 sufficient series of the East Indian G. cuspidatus for examination to 

 warrant me in making so positive a statement as to its distinctness 

 from G. A/ricanus, but the published descriptions indicate impor- 

 tant differences. 



In addition to the marked differences between G. A/ricamis and 

 G. Amerlcaniis in the number and character of the dorsal spines 

 and marginal plates, I wish to call attention to the following 

 points. G. Africainis (type) has no pedicellariae, above or below. 

 The actinal plates mostly have a central cluster of three to six or 

 more unequal rounded tubercles, much larger thaa the granules. 

 No specimens of G. Americamis that I have seen have this character, 

 though some of the largest ones may have one or two central tuber- 

 cles, on a few of the plates near the mouth. The granules of the 

 abactinal plates are much smaller than in the latter and are more 

 rounded, with less differentiation of the marginal series. The small, 

 intermediate abactinal plates seldom bear distinct rosettes of gran- 

 ules, but usually appear as small, round or otal, smooth-topped ossi- 

 cles, on a level with the other plates. 



In having the distal pair of doi'sal marginal plates larger and more 

 swollen than those that precede it, and largely in contact medially, 

 this species agrees with Pentagotiaster pulchellus and allied species. 

 I have seen no specimens of G. Americamis having this character, 

 nor is it said to occur in G. cuspidatus. 



It is my intention to fully illustrate these species in another arti- 

 cle, now in course of preparation. 



G. Africanns is native of the West Coast of Africa. 



G. Lainarckii [Astrogonium Lainarckii Milll. and Trosch., p. 56, 

 1842; Pentagonaster LamarcJcii Per. (Revis., p. 29, 1876) is from 

 an unknown locality. It has rounded dorsal marginal plates and 

 seems quite distinct from the other species. 



Pentagonaster Gray, 1840, 1866. Type P. pulchellus Gray. 



Stephanaster Ayi'es, Proc. Boston Soc. Nat. Hist., iv, p. 118, 1851. Type S. 



elegans Ayres=2nilchelliis Gray. 

 Pentagonaster (Sect. A, a, j^ars) Perrier, Revision, Arch. Zool., V., p. 12, 1876. 

 Astrogonium Sladen, Voy. Chall. , xxx, pp. 363, 285, 1889. 

 Stephanaster Perrier, Exp. Trav. and Talisman, p. 402, 1894. 



The name Pentagonaster was first introduced into binomial 

 nomenclature by Gray in 1840. By him it was definitely defined, 

 and a well-known species was given as the type (see p. 147, above). 

 Therefox'e, the name should be used for the group thus limited by 

 him. 



