12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 98 



replica of the bases of the adjacent arms, with small furrow spines 

 and small tube feet, set considerably below the general surface. 



The arm buds are situated as follows, clockwise from the madre- 

 porite ; the 2 larger in interradii 2 and 14, the 2 very small ones in 

 interadii 11 and 19. 



SCLERASTERIAS, sp. 



Locality. — Galapagos Islands : Tagus Cove, Albemarle Island ; 

 from the anchor chain in 50 fathoms (91 m.) of water ; July 26, 1938. 

 One specimen (U.S.N.M. no. E.5643). 



Notes. — The specimen at hand is small and young; R = 8.5 mm., 

 r = 2 mm. ; there are 6 arms, 5 of full size and the sixth in the form of 

 a well developed bud; there are 12-13 inferomarginal and 43 adambu- 

 lacral plates. 



Prof. Walter K. Fisher was so very kind as to examine this speci- 

 men for me. 



ECHINOIDEA 

 EUCIDARIS THOUARSII (Agassiz and Desor) 



Localities. — Galapagos Islands: Sulivan Bay, James Island; July 

 24, 1938. Two specimens (U.S.N.M. nos. E.5632, E.5633). 



Galapagos Islands : Elizabeth Bay, Albemarle Island ; July 26, 

 1938. One specimen (U.S.N.M. no. E.5634). 



Galapagos Islands : Post Office Bay, Charles Island ; July 27, 1938. 

 Seven specimens (U.S.N.M. no. E.5637). 



Notes. — One of the specimens from James Island (E.5632) is 

 the largest recorded for this species. The horizontal diameter is 76 

 mm., the height is 57 mm., and the longest spines are 68 mm. long. 



HESPEROCIDARIS HOUSTONTANA, n. sp. 



Plate 4, figs. 10, 11; plate 5, figs. 12-14 



Characters. — The interporiferous zone of the ambulacra is elevated 

 and is completely covered by the 2 marginal rows of large and the 

 2 inner rows of small tubercles ; the primary spines are about one-third 

 again as long as the horizontal diameter of the test and are slightly tap- 

 ering, slightly flattened, abruptly truncated distally, and carry 13 or 14 

 rows of granules which are low and evenly rounded on the oral side, 

 but rise into conical prominences on the aboral side. The new species is 

 most closely related to H. panamensis (A. Agassiz) from which, 

 however, it appears to be quite distinct. 



