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



same form, but rather smaller and more closely arranged. The 

 granules are higher than broad with a rounded top. 



Abactinal plates are covered with granules like those of the mar- 

 ginal plates. They are roundish 'and slightly convex, in contact by 

 their angles, between which some of them are slightly notched or 

 incurved, to make room for the papular pores. 



The madreporic plate is rather small, with many fine gyri. 



The granules of the actinal plates are well-spaced and rather 

 larger and more conical than those of the upper side ; they form a 

 marginal series, mostly of six to ten, which are somewhat divergent, 

 and surround one or two larger central ones, which are sometimes 

 replaced by a centi*al pedicellaria, having broadly spatulate blades, 

 rather higher than the granules. 



The two outer spinules or granules of the adambulacral plates are 

 like those of the actinal plates; there is often a minute conical 

 spinule on the proximal side of the larger central spine. 



Taken by the Albatross, off Florida, at station 1415, N. lat. 30° 

 44', in 440 fathoms, coarse sand, shells and foraminifera (No. 18,426, 

 one example). 



Subfamily MEDIASTERIN^, nov. 



This subfamily is proposed for those Goniasteridae that agree very 

 closely with the typical Goniasterinpe in the structure of the actinal 

 side and marginal plates, but have paxilliform abactinal radial 

 plates in the papular areas. These plates may be in the form of 

 protopaxillae or parapaxilla?, but are usually covered by close gran- 

 ules and not by spinules, but sometimes they are spinulose. They 

 stand a little apart, when denuded, and may appear stellate at base, 

 Mediaster and Nymphaster are the leading genera. In these there 

 are bivalve pedicellariae. 



In Mediaster, and probably other genera, these plates are united 

 by small dermal radiating ossicles that do not show distinctly at the 

 surface (see pi. xxvi, figure 8). In Nymphaster thei'e are no connect- 

 ing ossicles, but the columnar plates have enlarged and six-lobed 

 bases. Some of the forms placed here show strong aftinities to some 

 Pseudai'chasterinpe. 



Trans. Conn. Acad., Vol. X. August, 1899. 



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