SHALLOW-WATER STARFISHES 363 



Genus Allostichaster Verrill, nov. 

 Type, A. polyplax Miiller'and Troschel. 



It is diplacanthid and multiple-rayed, with one to five madreporic 

 plates, and is probably autotomous. The two rows of marginal plates 

 are stout and imbricated ; dorsal plates and spines form five somewhat 

 irregular longitudinal rows, several short, obtuse spines on each plate. 

 Minor pedicellariae are dermal, usually not circumspinal. 



SPINULOSA. 



The Echinasteridse are well represented by Henricia, several 

 species ; Poraniopsis, one species ; on the coast of Chile, by Echinas- 

 ter; at the Falkland Islands, by Cribraster sladeni Perrier. 



Henricia seems to have several species and subspecies, and these 

 vary much as do the northern species. 



H. obesa (Sladen, 1889) was described as from a depth of from 12 

 to 245 fathoms. Magellan Strait ; Falkland Islands. 



H. pagenstecheri (Studer) was originally from South Georgia. 

 Shallow water ( ?). 



H. hyadesi (Perrier 1891, as Cribrella), Clark, 1910, p. 337, pi. n, 

 fig. 5. This was recorded by Perrier from Fuegia, etc., and by Clark 

 from Chile (ex. Meissner) ; 35 to 200 meters (Perrier). 



H. studeri (Perrier, 1891), from Magellan Straits, in 9 to 183 

 meters. 



Ludwig, 1905, seems to consider all these as variations of H. pagen- 

 stocheri. To me most of them seem as distinct, if correctly described 

 and figured, as some of them are from the corresponding Arctic 

 forms. These species of Henricia are all pretty closely related to the 

 northern and Arctic species, contrary to those of the Asteriidse. 



Cribraster is known only from the Falkland Islands; depth not 

 known, probably littoral. C. sladeni Perrier, 1901 (p. K, 104, pi. xi, 

 figs. 2a, 2b, and Appendix, p. K, 161). 



Echinaster antonioensis Lor., 1904, and E. lepidus Lor., 1904, have 

 been described from the Gulf of San Mathias. E. lepidus is said to 

 lack interradial papular pores, and in that case it belongs to Rhopia 

 Gray, near R. sepositus, of the Mediterranean. The former species 

 is related to E. brasiliensis. 



Poraniopsis echinaster Perrier, 1891 (p. K, 106, pi. x, figs. 2, 20, 

 95 meters). This is nearly related to P. inflata Fisher, from the 

 North Pacific. 



Poraniopsis mira (=Lahillia mira de Loriol, op. cit., 1904, p. 33, 

 pi. HI, figs, i-i/i). 



