284 VERRILL 



makes it a family of Spinulosa. The reasons for this are not very 

 evident, for Valvaster has a series of large, broad, valvular pedicel- 

 lariae on the supermarginal plates, which are not otherwise found 

 in the family Echinasteridse, nor in the order Spinulosa. Moreover, 

 it has erect bivalve pedicellariae on the actinal and adambulacral 

 plates, with large marginal plates in two rows, and is, therefore, 

 phanerozonate. These characters and its jaws and odontophore 

 indicate that it belongs to the suborder Valvulosa. 



It should, in my opinion, form a separate family, Valvasteridae, 

 near Ophidiasteridae, but peculiar in having the dorsal ossicles reticu- 

 lated and bearing solitary spines in longitudinal rows. Odontophore 

 with articulating tubercles, as in Ophidiasteridse ; jaws pointed. 

 Actinal plates bear flattened spines. The ambulacral suckers have a 

 rosette of calcareous deposits. 



The former subfamily Mimasterinae I have here raised to the rank 

 of a family, to include only the genus Mimaster, which seems to be 

 a rather isolated form. 



The families of the above list represented within our limits are 

 Nos. I, III, VI, VII, X, XI, XIII, XIV. 



Suborder VALVULOSA Verrill = VALVATA (Perrier), 



emended. 



Valvulatce (order) PERKIER, Nouv. Arch. Mus. Hist. Nat., vi, 1885. 

 Valvata (order) PERRIES, Exped., Trav. et Talism., pp. 22, 23, 28, 29, 1804. 

 Valvata (suborder) VERRILL, Revision, Trans. Conn. Acad., x, p. 200, 1899. 



This extensive group includes starfishes with stellate or pentagonal 

 forms, usually rather stiff in appearance, and nearly always five- 

 rayed, in which the dorsal plates are most commonly tesselated and 

 granulated, or else take on the character of protopaxillae or pseudo- 

 paxillae. Sometimes they are naked ; often spinose ; very rarely truly 

 paxilliform ; sometimes covered by a thick, smooth, or granulated 

 integument. 



The various kinds of abactinal ossicles pass into each other by 

 various intermediate forms, so that it is impossible to draw any very 

 strong or sharp family lines on this character alone, though the 

 character of the plating may generally be taken as of generic value. 

 Sometimes they are openly reticulate; rarely (Asteropidae) they are 

 partly abortive. 



Pedicellariae are often lacking ; when present they are usually 

 valvular, foraminate and sessile, or fossate. The valves are either 

 granuliform, or large and broad, or narrow and spoon-shaped, 

 plataleiform, spatulate, or battledore-shaped, rarely papilliform. 



