STAEFISHES OF THE PHILIPPINE SEAS. 117 



Station 5290, near type-locality, 214 fathoms, lava, gravel. 

 Station 5365, Balayan Bay, Luzon, 214 fathoms. 

 Station 5550, vicinity of Jolo Island, 258 fathoms, fine sand, shells, 

 bottom temperature 52.3° F. 



PERSEPHONASTER ANCKISTUS Fisher. 



Plate 26, fig. 3 ; plate 27, fig. 2 ; plate 30, figs. 4, 4a-d. 

 Persepkonaster anchistus Fisher, 191oa, p. 614. 



Diagnosis. — Similar to P. euryactis, but with slightly slenderer 

 rays which taper evenly on the outer part to an attenuate extremity; 

 actinal inf eromarginal spines lacking except on the first few plates ; 

 superomarginal spines lacking on first 3 to 5 plates, and distally 1 

 to 3 in number ; lateral comb of spines as in euryactis, but the second 

 comb very poorly developed, usualh'' represented by a single spine, 

 behind one of the top spines of the first comb ; paxillae arranged as 

 in ewyactis and of about the same size, but with slightly longer 

 spinelets; abactinal pedicellariae numerous, with jaws only slightly, 

 sometimes not any, thicker than the surrounding spinelets; subam- 

 bulacral spines slightly more numerous than in euryactis, in 2 or 3 

 longitudinal series. R=143 mm., r=34 mm., R=4.2 r; breadth of 

 ray at midinterbrachium, 34 mm. 



Description. — The spinelets of paxillae usually stand erect, forming 

 a flat-topped, compact 4-sided or rounded group. A rather large 

 paxilla has 15 to 20 slender terete, blunt peripheral spinelets and 8 

 to 12 central ones, of which 3 or more are often slightly swollen a'nd 

 curved to form the jaws of a fasciculate pedicellaria. Abactinal 

 plates elliptical, but with slightly undulating margin — not quite so 

 obviously nicked or scalloped as in euryactis. 



Superomarginal plates, 48 to a ray in the type, have the same pro- 

 portions as in euryactis^ and the type has usually 3 spines in a simi- 

 lar position except on the first 2 to 4 plates. Sometimes there are 4 

 or 5 spines. The central is the largest, and proximally is about as 

 long as the plate, but distally is one and a half times. The specimen 

 from station 5116 has usually only 1 spine not so long as its plate. 

 The general covering of the plate is similar to that of euryactis. 



Inferomarginals about the same proportions as in euryactis., but 

 lacking the actinal continuation of the lateral comb except on the 

 first 2 to 6 plates where actinal spines occur irregularly. This dif- 

 ference is the most striking one between euryactis and anchistus. 

 The lateral comb has proximally 4 or 5 prominent appressed spines 

 and distally 2 to 4. Underneath these there is often a single spine, 

 the rudiment of the second lateral series. In the type the squami- 

 form spinelets are much as in euryactis, though -in the specimens 

 from Balayan Bay they are much slenderer and pointed not truncate 

 13434— Bull. 100—19 9 



