A L C Y O N I U M. 179 



fomething lingular in the contraction and dilatation of the 

 opening of the outward fkin over the holes at the fmaller 

 end of the rays. We cannot confider this as a mouth, 

 when at the fame time it is agreed that the holes on the 

 broad end of the rays are mouths ; fo that the ufe of this 

 central hole muft be left to future obfervation, when it is 

 fufpe&ed it will be found to be a new genus. 



c. Alcyonium mammil- A1 . .,,.,_, „ 



\ r Alcyonium with little feats. * AB - '■ 



loiuim y Fig. 4.51 



Alcyonium albidum co~ This whitifn leather-like 



riaceum,mamillis co?ivexis: Alcyonium is fpread over 

 centro cavo fubJiellatO) co- rocks, with many convex teat- 

 adunatis. like figures, hollow in the 



middle, with a faint ftar-like 

 appearance, and united clofe 

 together. 



Tab. 1. Fig. 4. 5. 



Lapidis AJirottidis Jive ftellaris frimordia. Sloane Hi ft. 

 Jam. Vol. 1. tab. 21. fig. 1. 2. 3. 



Sir Hans Sloane, who has given a figure of this and the 

 following Alcyonium in his Hiftory of Jamaica, takes it 

 to be the beginning of the Aftroite Coral : but the foft- 

 nefs of the fubftance, of which it is compofed, (hews it 

 to be of a different genus. The Weft-India iflands afford 

 us feveral varieties of this kind. Each mamilla, or cell, 

 has a polype within it, adhering to its bafe by twelve fila- 

 ments, which anfwerto as many tentacula when they ex- 

 tend themfelves. 



Fig. 4. is the natural fize of a piece of this Alcyonium ; 

 fig. 5. is the figure of. two cells opened perpendicularly to 



A a 2 mew 



