334 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



present, however, we may retain the species in the Chilean fauna, with the hope 

 that further collecting on the South American coast may settle the doubt con- 

 cerning it. 



Asterina chilensis. 



Asteriscus chilensis C. F. Liitken, 1859. Vid. Med. f. 1859, p. 61. 

 Asterina chilensis C. F. Lutken, 1871. Vid. Med. f. 1871, p. 302. 



Plate 2, figures 3 and 3. 



This pretty starfish, which may be as much as 50 mm. in diameter, is one of 

 the characteristic species of the Chilean fauna, arid has been recorded from many 

 places along the coast between Payta, Peru, and Talcahuauo, Chile. In the 

 Coker collection there are specimens from La Punta (at Callao), Lobos de 

 Afuera Islands (southwest of Aguja Point) and Bay of Sechura (just north of 

 Aguja Point), but unfortunately there are no notes on coloration or habits. The 

 specimens vary greatly in form, from R= 1.5r to R = 2r and in the spinula- 

 tion of both the upper and lower surfaces ; in some specimens the spinules on the 

 upper side seem rather long, while in others they are more like granules ; the plates 

 of the actinal side carry in some cases only 2 or 3 spines, in others 4-6. 

 There is also a striking difference in the color ; one group of specimens are uni- 

 formly dull yellowish or pale brown, while another shows very bright colors, min- 

 gled blue and red. The latter are from the Bay of Sechura and were at first 

 supposed to represent a different species, bnt unfortunately for that view they do 

 not agree with each other in proportions and spinulation, nor differ consistently 

 in any character but color from the individuals taken south of Aguja Point. It 

 seems therefore that chilensis is a variable species, the limits of whose variation 

 have still to be determined. 



Parasterina obesa, sp. nov. 1 



Plate 3, figures 1 and 2. 



Rays 5. R = 42 mm., r = 14 mm., R = 3r. Interbrachial arcs rounded. 

 Rays very stout, tapering slightly to a blunt point; breadth at base, 13 mm., 

 vertical thickness 10 mm. Disc large and flat, its vertical diameter the same as 

 that of the rays. Whole surface of disc, interbrachial spaces and rays, above and 

 below to the adambulacral series, covered by paxilliform plates very much like 

 those in Odontaster singularis, which carry crowded groups of 10-50 blunt, granule- 

 like spinelets. Along sides of rays, and especially on under surface and in 

 interbrachial areas these plates are in regular longitudinal and diagonal series, but 

 dorsally no such regular arrangement is to be seen. Plates in oral interbrachial 

 areas, largest and most widely spaced from each other, with 6-12 spinelets each. 

 Papulae occur singly or in groups of 2-4, between dorsal plates and along sides 

 of rays but not on lower surface. Neither supero- nor infero marginal plates can 



1 obesus, fat, in allusion to the very plump rays. 



