210 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



.45— .55 h. d., almost uniformly covered with small tubercles; the uarrow porifer- 

 ous zones, about .20 of ambulacra, and the numerous small tubercles on the 

 interambulacra. This species ranges from Havana to Barbados in 197-150 fths. 



Dorocidaris rugosa, sp. nov. 



Plates 4 and 5. Plate 7, figs. 5-8. 



Test rather high, vertical diameter about .60 h. d. ; coronal plates 7; areolae 

 deeply sunken and distinct; median interambulaeral area very fully covered with 

 tubercles, smallest next to vertical suture, which is quite distinct; ambulacra less 

 than one-third of interambulacra in width ; poriferous zones narrow and deeply 

 sunken ; median ambulacral area with a double series of marginal tubercles, inner 

 much smaller, and between these some small scattered tubercles tend to conceal 

 vertical suture ; pores oblique, small. Abactinal system about .45-50 h. d., irregular 

 in outline, stout and heavy somewhat as in Stereocidaris, covered with rather 

 coarse tubercles ; genital plates somewhat pentagonal, with lateral margins con- 

 cave, and pores not far from centre; ocular plates more or less pentagonal, usually 

 wholly excluded from anal system, but posterior ones sometimes in contact with 

 anal plates, more or less notched on outer edge by ambulacra; anal system not 

 quite one-half of abactinal, with an external series of 10-12 large plates and 12-15 

 smaller ones at centre ; except along margins all plates of abactinal system covered 

 with rather coarse tubercles of nearly uniform size ; each genital plate has 50-60 ± 

 such tubercles and each ocular plate 20-30 ±. Actinostome small, about .40 h. d., 

 not at all sunken, closely covered with stout plates, 5 in each interambulacrum 

 and about 10-12 pairs in each ambulacrum. Primary spines long, 2-2.5 h. d., 

 terete, usually swollen just above collar, and thence tapering to tip, covered with 

 12-16 longitudinal series of conspicuous sharp granules ; actinal primaries slightly 

 flattened, a little curved and somewhat serrate; secondaries not peculiar, of mod- 

 erate length and width, flat, blunt, or truncate at tip. Pedicellariae as in papillate. 

 General color of test yellowish or brownish, more or less rose-red or brick-red, 

 abactinally ; secondaries and miliaries same as test; primaries whitish or grayish, 

 abactinal ones sometimes bright rose ; neck smooth, polished, white, brownish, or 

 pink ; collar narrow, pale brownish or rarety lighter than neck. Largest specimen 

 in the Museum of Comparative Zoology, 40 mm. h. d. ; vertical diameter, 24 mm. ; 

 abactinal system, 20 mm.; actinostome, 17 mm.; longest primary, 80 mm., 5 mm. 

 thick near base, somewhat more than 1 mm. thick at tip. In the National Museum 

 is a fine specimen 60 mm. h. d. 



This species is clearly the representative of papillata in the western Atlantic, 

 but may be readily distinguished from that species by the broader and more com- 

 pletely covered median interambulaeral area, the mucli more fully tubercled 

 median ambulacral area, the more uniformly tubercled abactinal system, and the 

 terete and very prickly primary spines. The distribution of rugosa is only 

 imperfectly known ; the specimens I have examined are from stations between 

 32° N. lat. (off Savannah, Ga.) and Barbados and St. Vincent, in 164-337 

 fathoms. There are 8 specimens in the collection of the U. S. National Mu- 

 seum, several of which have been labelled by Mortenscn. One (No. 21,444) 

 is labelled " Stereocidaris ingolfiaua," which is a very natural mistake, as small 



