476 SALMACIS SULCATA. 



Philippine Islands ; Siam ; China. 



Salmacis sulcata 



! Salmacis sulcatus Agass., 184G, C. R. Ann. Sc. Nat., VI. 



PI. VHP.f.s; PL VI. f. e. 



This species is very closely allied to S. bicolor. It differs from it in having 

 a more deeply lobed and slightly larger actinostoine. The abactinal system 

 is less prominent; the genital plates are pointed, shallower; the ocular 

 plates approach the anal system, and carry two prominent tubercles on 

 each side of the ocular pore ; the anal system is large. In the interambulacral 

 space we find one of the vertical rows above the ambitus much larger than 

 the others; the remaining part of the coronal plates is occupied by small 

 secondaries and miliaries, forming two somewhat irregular horizontal rows. 

 sometimes three, near the ambitus, in striking contrast with the uniform 

 tuberculation of S. bicolor. The tubercles of the actinal side arc uniform 

 in size and larger than those above the ambitus, as in S. bicolor, but not 

 as closely crowded and with larger secondaries. In the ambulacra] space 

 the two vertical rows of primaries adjacent to the poriferous zone are com- 

 paratively smaller than those of the interambulacral region. The horizontal 

 furrows of the coronal plates are better defined in this species than in S. 

 bicolor. The sutural pores are slightly larger. The test, when dry, is yel- 

 lowish-green, with spines of the same color at the base, tipped witli dark 

 violet ; the spines are comparatively sharper and more uniform in size above 

 and below the ambitus than in 8. bicolor. Actinostome somewhat more 

 sunken also than in that species. Madreporic genital much larger than the 

 other genital plates. In other specimens the spines were cream-colored, 

 banded transversely by five or six narrow dark brown lines. Young speci- 

 mens of Salmacis sulcata figured by Savigny would readily be mistaken for 

 young Echinus, as the difference in size in the vertical rows of the primary 

 tubercles is not seen at that age. 



Australia ; Philippine Islands ; Mozambique ; Red Sea. 



