SUPPLEMENT. 707 



POLYTREMA MINIACEA. 



P. miniacea minima, subtiliter ramoso-divisa. 



Bright red ; minute, and minutely ramoso-subdivided. 

 Mediterranean Sea. 



This species is found attached to shells forming minute tufts, one to 

 three lines broad, and about the same in height. 



Millepora miniacea, Pallas, Zooph., 251. , Deslongchamps, Encyc., 546. 



, Esper, i. 225. Polytrcnia corattina, Risso, Merid. Eur., 



, Oken's Zool., i. 62. v., 340. 



Millepora rubra, Ellis and Solander, 137. Polytrema miniacea, Blainv., Man., 410. 

 , Lamk., ii. 309, No. 8. 



The following are probably distinct species, though usually referred 

 to the miniacea. 



/3. crustula. Surface either smooth or somewhat gibbous or pustu- 

 lous; colour very deep red; often six to eight lines broad, surface 

 punctate, the punctations dull, and other parts shining. From the 

 West Indies. (Esper, i., Mill, tab. 17 ; and Blainv., Man., pi. 69, 

 fig. 4.) Fig. 2, plate 61, natural size; 2 a, surface, enlarged. 



ft. echinulata. Surface minutely pustulous, or covered with deli- 

 cate echinuliform points, nearly a line high, and having one or more 

 cells about the summits. Plate 61, figs, !,!,] b, natural size; 1 c, 

 1 c/, some of the prominences, enlarged ; 1 e, a transverse section, en- 

 larged. From the Pacific. Exp. Exp. 



POLYTREMA BRUNNESCENS. (Dana.} 



P. pallide brunnescens, crasse incrustans, cavernosa, super -fide gibbosa, 

 et lacerata, et valde irregulari. 



Pale brownish; thick incrusting, cavernous, surface gibbous, lacerate, 

 and very irregular. 



Plate 61, fig. 3, natural size. 



Society Islands. Exp. Exp. 



The very ragged surface rises, in some parts, into slender points, 



