rOMPTOXTA ^O^rPTOXT. 69 



Geuns—COUFTO^IA, Gmn. 



Gray, 1840. Annals and Magazine of Natural History, vol. vi, p. 278. 

 — 1866. Synopsis of Starfishes in the British Museum. 



Body depressed, with produced tapering rays. Disc covered abactinally and 

 actinally mth numerous polygonal plates which possess a uniform gi'anulation. 

 Marginal plates numerous. Supero-marginal plates equal in luimber to the infero- 

 marginals, and forming a moderately broad border to the disc. Infero-marginal 

 plates (as well as all other plate?) devoid of spines. Radialia present throughout 

 length of ray. 



This genus apparently differs from Sfellaster only in the absence of spines on 

 the infero-marginaUa. It is thus similar to, as well as prior to Ofjmaster (von 

 Martem, 1865) and Dorif/onn {Gmij, 186G). 



1. CoMPTOxiA CoMPTOXi, Fovhes, sp. PI. XVII, figs. 3, 3(7, and oh; PI. XVIII, 



figs. 2, 2 a, 2h,2c,2 d. 



Stellaster CO.MPTOXI, Forbes, 1848. Mem. Geol. Surv. Gt. Brit., vol. ii, p. 476. 



— — Forbes, 1850. In Dixon's Geology and Fossils of the 



Tertiary and Cretaceous Formations of Sussex, 

 pi. xxii, fig. 8, p. 335. 



— — Lujardin et Hiipi', 1862. Hist. Nat. Zooph. fichin. (Suites 



a Buffon), p. 408. 



— — Forbes, 1878. In Dixon's Geology of Sussex (new edition, 



Jones), pi. xxii, fig. 8, p. 368, 370. 



Specific Characters. — Disc large and interbrachial arcs wide, gi^nng the disc a 

 distinctly pentagonal appearance. !Major radius rather more than twice the length 

 of the minor radius. Arms elliptical in cross section. Large valvate pedicellarife 

 present. 



Material. — Two specimens (the two cotypes) of this species are in existence. 

 One (formerly in the Bowerl)ank Collection) displays the actinal aspect (PI. XVI 1. 

 fig. 3), and is preserved in the British Mu.seum of Natural History (34311). 

 The other (PI. XVIII, fig. 2), which shows the dorsal aspect, is preserved in the 

 Northampton Museum. This is the specimen figured in Dixon. 



Description. — The large pentagonal disc is covered dorsally with numerous 



