432 Verrill, Notes on Radiata. 



heads. The polyp-spicula are mostly small, rather slender, oblono- 

 spindles, with blunt ends, closely covered with small rough warts. 



The single specimen from Cape St. Lucas has spicula which aver- 

 age somewhat larger, but agree well in form and appearance with 

 those of the P;inama specimens. 



The longer spicula measure 1-45""" by -400"'", 1-22 by -400, 1-17 by 

 •375, 1-15 by -375, 1-15 by -325, 1-12 by -375, 1-12 by -300, 107 by 

 •300, 1-05 by -350, 1-02 by '325, -850 by ^275; the stouter ones 1-47 by 

 •500, 1-02 by -400, I'OO by -375, •975 by "500, -950 by ^425, -900 by 

 •450, -750 by -300, '700 by ^375, -675 by -325, -650 by '350, -625 by •SOO ; 

 the small spindles -425 by -100, ^375 by •lOO, -350 by -125 ; the small 

 irregular, thorny spicula -275 by -175, -225 by '150, -175 by •100; the 

 stars -200 by ^200, -200 by -150, -175 by -175 ; the heads ^175 by ^150, 

 •175 by -100; the polyp-spindles •S 00 by •lOO, ^450 by ^112, ^450 by -075, 

 •425 by -125, '400 by -137, '400 by •lOO, ^375 by -100, -350 by -087, '325 

 by ^075, -300 by •lOO, ^250 l»y -075, "225 by ^062. The longer spicula 

 from the Cape St, Lucas example measure 1*67 by '550, 1*50 by -500, 

 1-50 by ^425, 1-50 by -375, 1'25 by •SOO, 1-12 by ^325 ; the stouter ones 

 1-60 by -550, 1^40 by "575, 1-30 by '500, 1^27 by -450, 1-25 by ^500, •875 

 by -450. 



Pearl Islands, rare, brought with 31. crassa and M. fniticosa from 

 6 to 8 fathoms by divers, — F. H. Bradley ; Panama, at extreme low- 

 water, on reef, very rare, — F. H. Bradley ; Cape St. Lucas, — J. Xan- 

 tus, from Smithsonian Institution ; La Paz, — J. S. Pedersen. 



This species resembles in color and general appearance 31. echinata 

 and 31. fruticosa^ but is quite distinct from both in its short, stout, 

 blunt spicula. From the latter it differs, also, in its much stouter and 

 less numerous branches and larger verrucse ; from the former in its 

 shorter, broader, and more conical verrucie and firmer texture. 



Muricsa retusa Verrill, sp. nov. 



Plate VIII, figure 8. 



Corallum dark ])urplish, dichotomous, sparingly branched, branches 

 rather thick, with large sub-conical verrucas, which are not crowded. 



The trunk forks near the base and, in the only specimen seen, each 

 main branch subdivides again at the distance of about an inch. One of 

 the secondary branches again forks at two inches from its origin, the 

 others remain simple and about two inches long. The branches 

 spread widely at first and are about equal in size throughout, the termi- 

 nal branches being a little enlarged toward the end. The verrucie are 

 rather large, stout, subcorneal, nearly as broad as high, not crowded. 



