18 Mr. A, E. Veiiill on some 



It clifFeis more from i?. nmrrayi \\\ respect to the under 

 surface, whieli, in tlie latter, is uniformly covered with small 

 miliary spinelets. Probably P. rosea, Daniels. & Koren, 

 may be identical with R. min'roj/i, tor it agrees clopcly in 

 spinulation on both sides, but its identity with G. hispidus, 

 Sars, seems to me very questionable. The latter is more like 

 Lasiaster viUosiis, Sladen, in having large superomarginal 

 plates, spinules segregated on the dorsal plates, &c. These 

 characters can hardly be considered as generic, and therefore 

 it seems that all these forms should be referred to Rhegaster, 

 as the earliest genus established for any of them. Thus 

 R. Inspidus would be the earliest species, with R. villosus a 

 probable synonym, while R. borealis, Verrill (1878), and 

 R. spimdosus, Verrill (1879), would be the next two in 

 order. Thu.«, either one of these two names would supersede 

 R. murrayi or R. roseus, should either prove to be identical 

 with the latter. In my article of 1895, the descriptive notes 

 added under borealis should have been put under spinulosus. 



Rhegaster spinulosus, Verrill. (PL I. fig. 2.) 



Po7-ania spinulosa, Verrill, Proc. U.S. Nat. Mus. vol. ii. p. 202 (1879). 

 Foraniomorpha sjnmdosci, Verrill, Expl. by the ' Albatross,' p. 542 

 (1885); Amer. Jouru. Set, vol. xlix. p. 339 (1895). 



This is a larger species, ranging from north of Cape Cod 

 to Cape Hatteras in 80 to 610 fathoms. It sometimes has a 

 radius of 80 mm. 



This differs from R. borealis especially in having large 

 flat inteiactinal plates *, covered with minute miliary spinules 

 or granules, except at the outer end, where there are often 

 two or three small, appressed, acute spinules in a row. The 

 inferomarginal plates have about ten to twelve small marginal 

 spinules in about two rows ; the upper surface is closely 

 covered with erect miliary spinules, as in allied species, and 

 the papular pores are numerous, in clusters, over the whole 

 dorsal surface and between the marginal rows of plates. 



Alarginaster, Perrier, 1881 ; 1881 (pars). Type, M. pecti- 

 natus, Per. — This genus, when established, included the 

 young of two generic tj pes : Sladen, 1889, designated the 

 lirtit as the type ; the second {M.echinulatus) diflers, among 

 other ways, in having a regular furrow-comb on the adanibu- 

 lacral plates, as i\\ Rhegaster, but the dorsal plates are invisible 

 and. have sparse spines, unlike the latter. 31. pectin at us is very 



* The term " iiiteractinal plates " is used in place of " intermediate 

 aclinals " for the sake of brevity. 



