SHALLOW-WATER STARFISHES 77 



dorsal spines increase in size toward the tips of the rays. Papulae 

 ing groups. Minor pedicellariae nearly as in A. ochracea and A. con- 

 ferta; major pedicellariae smaller and far less numerous than in 

 those species, but of similar short and stout form. Diameter, thir- 

 teen inches. 



" Habitat Shoalwater Bay, Oregon Coast. Northern Pacific Rail- 

 road Expedition. Dr. J. G. Cooper." 



Large photographs of the type of this species, which is still in the 

 U. S. National Museum, were furnished by Dr. R. Rathbun. They 

 indicate that the average radii are 60 mm. and 170 mm.; ratio, 

 about as 1 : 2.83. The rays taper rapidly from a broad disk. 



The slender adambulacral spines are compressed and much 

 crowded, one to a plate. The peractinal and synactinal spines are 

 mostly gouge-shaped, though often bifid at tip ; but on the distal half 

 of the ray, many are only sulcate and flattened. The dorsal surface 

 was very accurately described by Dr. Stimpson, as may be seen by 

 comparison with our figures of his type. 



This species is more nearly allied to P. ochraceus than to any 

 other. It differs in the peculiar gouge-shaped spines, in the more 

 open reticulation of the dorsal skeleton, and in the much smaller and 

 more slender dorsal spines. 



The locality given by Stimpson is the only one positively known 

 to me for this species. 



PISASTER BREVISPINUS (Stimpson). 



Plate XLI, figures i, 2 (type); plate XLIV, figures I, 2; plate XLV, figure i; 

 plate LXIX, figure 3; plate LXXVI, figures i-ib (details). 



Asterias brevispina STIMPSON, Journ. Boston Soc. Nat. Hist., vi, p. 88, pi. 



xxm, fig. 3 (ventral spines), 1857. 

 Pisaster brevispina VERRILL, Amer. Journ. Sci., xxvin, p. 63, 1909. 



The original description by Dr. Stimpson is as follows : 

 " Rays five, each equalling in length twice the diameter of the disk. 

 Upper surface covered with very short, blunt, nearly uniform spines, 

 moderately numerous, sometimes forming an irregular row along 

 the middle of the ray, and showing a tendency to reticulation on the 

 sides. Beneath, there is a single row of slender ambulacral spines, 

 which are blunt and somewhat irregular in length; between these 

 and the marginal channel there are four rows of short compressed 

 spines, gouge-shaped, or notched by an oblique concavity at their 

 truncated extremities. Madreporic body large. Color yellowish. 

 Diameter, six inches. Taken from a sandy bottom in ten fathoms 

 near the mouth of San Francisco Bay." 



