286 BULLETIN 76, UNITED STATES NATIONAL MUSEUM. 



for me, found typical large individuals common at low tide along the rocky shores, 

 where they occurred in pot holes attached to rocks, or kelp, and nearly always 

 submerged. With them were numerous small specimens comparable to the dwarf 

 forms so common at Monterey Bay. 



HENRICIA LEVrnSCULA MULTISPINA Fisher. 

 PI. 72, figs. 1-4; pi. 73, figs. 1, 2. 

 Henricia leviuscula multispina Fisher, Zool. Anz., vol. 35, March 2!), 1910, p. 571. 



Diagnosis. — General form very similar to that of H. letnuscula but the abactinal 

 plates more compactly placed, usually smaller and more numerous; the papular 

 areas smaller; the spinelets very numerous, delicate, longer than in leviusnda 

 and ending typically in three or four (sometimes more) slender, very sharp points 

 or awns; adambulacral plates with numerous (twenty-five to fifty) spinelets, and 

 typically with two spinelets on the furrow face beyond the middle of ray; proximally 

 only one; actinal intermediate series of plates extending one-half to three-fourths 

 length of ray, not whole length as in leviuscvla. 



Description. — Raysfive. R = 8S mm.; r = 15 mm.; R = 5.8r. Breadth of ray 

 at base, 18 mm. Rays as a rule rather slender, long, gradually tapering. Abactinal 

 plates rather variable in size, but typically smaller and more compactly placed 

 than in E. leviuscida. The spine-bearing surface of plate raised and convex as in 

 leviuscvla; the spinelets are numerous, close-set and bristling, overhanging more 

 or less the papular areas. They are very delicate and glassy when dried, and 

 terminate in three to several sharp awns or points. The spinelets form a very fine 

 close velvety nap all over the surface of the body. It is not possible to count the 

 spinelets with much accuracy, but there are forty to sixty (frecjuently more) on the 

 median abactinal plates. Dorsally there are two to five papulae to an area, laterally 

 and actinally three to one. 



Superomarginal, inferomarginal, and actinal intermediate plates form ttiree 

 regular series as in leviuscula and have also the same relative proportions, but the 

 intermediate series extends only one-half to three-fourths the length of ray. As a 

 rule the superomarginals are abruptly larger than the dorsolateral plates just above. 

 Inferomarginals are conspicuously elongated transversely, usually about twice as 

 wide as the actinal intermediate plates (those adjacent to adambulacrals). The 

 intermarginal plates are variable; sometimes they are confined to a small triangular 

 area at base of ray and sometimes extend halfway along ray as a regular series of 

 small roundish pseudopaxillae; occasionally a second row is present extending nearly 

 or quite as far as the first. Therefore the superomarginal series is bent upward 

 j)roximally at the interbrachial angle, while the inferomarginals (as in levi-mcula) 

 run parallel to the actinal intermediates to the mouth angle. Between these 

 legular series are series of papular areas (except between adambulacrals and actinal 

 intermediate rows where papula? are present only on disk) with commonly two or 

 three papulae to an area in large examples. The spinelets of the marginal and 

 actinal plates arc similar to those of the abactinal surface, and the plates are com- 

 pactly placed. 



