146 BULLETIN 76, UNITED STATES NATIONAL MUSEUM 



The BuperomarginaJ spines are similar to those of forma troschelii, but often 

 not so regular. They partake of the character of the abactinal spines, varying in 

 robustness, but falling behind the abactinal spines in thickness. They vary from 

 cylindrical to capitate, truncate, the tip being striated, and sometimes asymmetrical 

 and oblique. Spines are usually single, but often accompanied by one or two, much 

 smaller, slender, slightly tapered. Very much less commonly there are two or three 

 subequal spines, but the specimens are not typical in other ways. 



The inferomarginal spines are slenderer and longer than the superomarginals, 

 more or less clavate and bent, one or less often two to a plate. Proximally there are 

 three series of actinal plates, with three series of spines. In some specimens many 

 of the actinals are diplacanthid, so that the armature is crowded. I have not been 

 able to find any distinctive difference in the inferomarginal or actinal spines, since 

 the individual and ago variations are very confusing. The third or inner actinal row 

 of plates is short as a rule. 



Adambulacral spines very similar to those of troschelii, generally alternating 

 one and two to a plate, with two on a few plates following the adoral carina. They 

 are typically slender, subterete, blunt (or slightly tapered in the case of the alternate 

 furrow spine). In some heavy-spined examples they are narrowly spatulate, with 

 a shallow groove at end. Adoral carina composed of three to six contiguous pairs 

 of adambulacral plates in specimens with R 120 to 150 mm.; in specimens having 

 It (JO to 70 mm. there are usually three pairs in contact. The broader rayed examples 

 appear to have the fewer number in contact. 



Actinostome very small, mouth plates closely similar to those of troschelii, having 

 two unequal apical spines and a longer, slender suboral. 



Papulae very abundant, completely filling the spaces between spines and masking 

 the small ones in alcoholic specimens. 



Crossed pedicellariae (pi. 58, figs. 2, 2a-2c) vary somewhat in minor details 

 and increase slightly in size in specimens from Unalaska. Monterey specimen; 

 length, 0.225 to 0.24 mm.; Puget Sound, 0.23 to 0.24 mm.; Unalaska, 0.31 to 0.34 

 mm. — all abactinal. The actinal and adambulacral are somewhat larger. 



Straight pedicellariae (pi. 58, fig. 5) of small size and lanceolate in form, similar 

 to those of typical troschelii, are fairly abundant in most specimens in the inter- 

 marginal, interbrachial, and actinal channels, along the furrow face of the adam- 

 bulacral plates, and on the adambulacral spines; absent or very scarce on abactinal 

 surface. 



Color in life very variable. Notes made at Departure Bay, British Columbia. 

 Red phase: (a) Clear flame scarlet, the spines and a very narrow surrounding zone, 

 pale cream color, (b) Vermilion, spines Saturn red to orange; or orange vermilion 

 above, larger spines and collars of pedicellariae, white, (c) Chinese orange, spines 

 yellowish white, (d) Brick red (Indian red), spines whitish, (e) Dragon's blood 

 red. 



Brownish phase: (a) Yellowish dark russet, spines paler, (b) Russet to burnt 

 umber; disk mottled with wood brown; spines whitish; skin flecked with pale Nile 

 blue, (c) Papulae deep ferruginous; spines whitish with basal zone of bluish gray. 

 (d) Mottled rich brown and gray; spines pale blue gray. These are pretty generally 

 pale clay color or faded yellow below. 



