484: A. E. Verrill — Revision of the Genera of Starfishes 



small spinules. A few small, rounded ossicles, with similar 

 spinules, are interpolated, usually one or two to a papular pore, 

 but none in the interradial areas, beyond the papular region, 

 where the plates become rounded or shield-shaped and bear a 

 small cluster of spinules. 



The inferomarginal plates are small and irregularly placed, 

 smaller and less prominent than the upper ones. Papular pores 

 form about twelve rows. 



To this genus, besides the type, belong the following species : 



P. exigua (Lara.) = A. pentagonus (M. & Tr.) ; = A. kraussii 



(Gray). Cape Good Hope ; East Indies. 

 P. calcar (Lam.). Australia. 

 P. fimbriata (Per.). Bourbon I. ; Magellan Str. 

 P. squamata (Per.). Senegal. 

 P. calcarata (Per.). Chili. 

 P. pusilla (Per.). Chili. 

 P. gunnii (Gray). New Zealand ; Australia. 



Desmopatiria Yer., gen. no v. 



This very peculiar starfish, of which the principal generic char- 

 acters are given in the table, p. 481, is remarkable for the peculiar 

 alveolar structure underlying the plates, above and below, and 

 in the interradial areas extending from the dorsal to the ven- 

 tral plates, as tubes. It is possible that in life they contained 

 calcareous deposits that have been dissolved by the acidity of 

 weak alcohol, for the ventral spinules appear corroded in many 

 places. 



Aside from this structure the dorsal skeleton is peculiar in 

 having very numerous linear plates, with smaller, roundish, 

 closely granulated flat plates, not overlapping nor imbricated ; 

 and in the irregular clusters of webbed spines on the ventral 

 plates. 



The dry specimen has the disk swollen and distorted and the 

 rays strongly curved upward, showing unusual flexibility in life. 



Desmopatiria flexilis Ver., sp. nov. 



Form stellate, with five short, broad rays. Disk swollen, in 

 the central and radial areas ; margins thin, with small marginal 

 plates, about the size of adjacent dorsals and closely granulated 

 in the same way ; the lower ones are the more prominent. 

 Radii, I7 mra and 26 mm ; ratio, 1:1*53; elevation in middle of 

 disk, 15 ram when dry. 



The larger dorsal plates of the wide radial areas are narrow, 

 transversely elongated, often in transverse series, partly nearly 

 straight, but often bent, closely crowded together but not over- 

 lapping, and with narrow grooves between them. Between these 



