88 VERRILL 



spines form only four or five rows, though similar in size. On the 

 distal half of all the rays the ventral rows decrease to about four to 

 six, the plates bearing only two spines, or but one. 



The ventral spines are unusually crowded proximally. They are 

 also longer and less stout, though mostly blunt, except the syn- 

 actinals and those on and near the interradial areas, where many of 

 them become decidedly longer and acute. Many in the synactinal 

 row are deeply grooved on the outside, and the distal ones become 

 more slender and subacute. The adoral spines are long, slender and 

 acute. 



Large serrate major pedicellariae are scattered over the dorsal 

 and lateral surfaces, but are not half so numerous as on the other 

 large specimen. 



The dorsal spines are less numerous, larger, more acute, and more 

 regularly spaced, their average intervals being 8 mm. to 10 mm. 

 wide. 



Minor pedicellariae form dense wreaths around all the dorsal and 

 upper marginal spines. 



Off Pacific Grove, California (Dr. W. R. Coe, 1901). 



PISASTER LUTKENII Var. AUSTRALIS Verrill, nov. 

 Two very large specimens (c, d) of this variety are in the Museum 

 of Yale University. One has the radii 56 mm. and 252 mm. ; ratio, 



1:4-5- 



The oral adambulacral spines are one-fourth longer than those of 

 the mid-ray ; they are long, slender, regularly tapered. The ventral 

 spines, near the base of the rays, are in four and five crowded rows ; 

 but on the mid-ray there are about four regular rows ; those of the 

 inner and middle rows are very stout and blunt, often nearly as thick 

 as long, irregular in form, often pinched, lobed, or sulcated, and 

 sometimes slightly bifid; the tips are often clavate, swollen, or 

 truncate. 



The inferomarginals, or two outer rows, and those near the 

 mouth, are longer, not so stout, and more regular, mostly with 

 obtuse or ovoid tips. Distally they become longer and more fusi- 

 form, and many are deeply channeled on the outer side. 



The inferomarginal spines stand two on a plate, nearly or quite 

 to the tips of the rays, and thus form the two outer rows of ventral 

 spines. There are proximally three rows of stout actinal plates, each 

 usually bearing a single spine, thus forming three rows; the first 

 row (peractinal) extends to the tip of the ray; the third row (syn- 

 actinal) only extends to about the distal third of the ray. 



