144 BULLETIN 76, UNITED STATES NATIONAL MUSEUM 



from Monterey Bay, lowest tide (some specimens); from stations 3461 and 3464 

 (Straits of Fuca); 3053 (off Oregon); Naha Bay, Alaska (small specimens). In the 

 largest example (from station 3466, Straits of Fuca, pi. 68, fig. 1), corresponding to 

 the first easily counted 25 inferomarginals, there are on the five rays the following 

 numbers of superomarginal spines: 19,15; 15,12; 19,16; 19,18; 15,18. On the 

 distal half of the ray superomarginal spines occur on nearly every plate, and near the 

 tip are crowded into a zigzag line. Other specimens, for instance two from lowest 

 tide, Monterey Bay, tend to skip alternate plates proximally, but not with any 

 regularity. In the beautifully preserved specimen from station 4202, the condition 

 on two rays selected at random will show the variation. Corresponding to the first 

 easily counted 25 inferomarginal plates there are the following number of supero- 

 marginal spines: 20, 22; 20, 18. In the small specimens from Naha Bay (pi. 70, 

 fig. 3) there is more nearly a true alternation with 13 or 14 superomarginal spines to 

 25 inferomarginal plates. In contrast to this is a slender rayed form from Monterey 

 Bay with 22 superomarginal spines to 25 inferomarginal plates (forma montereyensis) ; 

 and one from station 3445, 100 fathoms, Straits of Fuca, with 25 superomarginal 

 spines to the same number of inferomarginal plates (forma leptostyla). 



The form which is sometimes found at the lowest tide in rocky situations in the 

 vicinity of Point Pinos, Monterey Bay, and along the rugged coast at the mouth of 

 Carmel Bay, to the south, is sensibly different from the British Columbian forms. 

 The rays of the Monterey form are long and average slenderer, while the spines are 

 usually much heavier (except as compared with forma biordinata) with somewhat 

 heavier sheaths. There are usually more numerous superomarginal spines, and the 

 dorsolateral spines are less widely spaced on the proximal third of the ray. But all 

 these items have their exceptions. 



So far as the spines are concerned, three specimens from Monterey Bay (forma 

 montereyensis) exhibit the extreme of robustness, with the single exception of a speci- 

 men from Port Renfrew, Vancouver Island (forma biordinata). In example one 

 (R 107 mm.) the longest spines are 3 mm., by 1.2 at base, and the tip is capitate, well 

 rounded, and scored by upward of 25 well-marked grooves. The spines resemble 

 those of Pisaster giganteus somewhat. (PI. 67, fig. 3, 3a, right-hand figures.) The 

 second specimen has the spines slightly longer, scarcely swollen, and with fewer 

 shallower furrows at the tips. In a third example (with R 150 mm.) the longest 

 spines are 4.5 mm., by 1 mm. at base. (PI. 67, figs. 3, 3a, left.) Some of them taper 

 slightly, then at about mid-height swell slightly, to taper a trifle again to an obtuse 

 tip, this distal portion having upward of 15 shallow grooves. These spines are 

 distinctly stouter than those of the Yes Bay specimen, although the latter, is larger. 

 But in a fourth specimen collected at lowest tide, Point Pinos, the abactinal spines 

 are as slender as in the type forma, 4 to 4.5 mm., by 0.75 mm. at base, and taper 

 gradually to a blunt tip, which is not furrowed. 



There appears to be a very definite physiological difference between these Monte- 

 rey specimens and those from Vancouver Island (both the typical form and forma 

 biordinata). The northern specimens shed their rays very easily and are rather diffi- 

 cult to preserve well. The Monterey form is not at all difficult to preserve and does 

 not detach its rays readily. I have handled both sorts, alive, and have kept the 

 Monterey form in aquaria where it is fairly active and eats a variety of food includ- 

 ing dead squid, crabs, and fish. 



