SUBORDER ALCYONARIA. 627 



/3. arborescens. Dendroid, trunk stout and elongated, with many lateral branches; 

 polyp-bearing ramuscules, one and a half to four lines thick ; expanded polyp-star half a 

 line broad, papillm of the tentacles minute, in two or three series; spicula of the ramuscules 

 one and a half lines exsert ; colour, crimson or orange, also, white, with the ramuscules 

 orange or crimson. (Plate 59, fig. 4, part of a zoophyte, natural size ; 4 a, one of the 

 polyps, magnified, and an exsert spiculum, &c. ; 4 b, section of stem ; 4 c, surface en- 

 larged, showing the spicula ; 4 d, spicula enlarged; 4 e, spicula polished down thin, and 

 enlarged, showing internal texture.) 



This species hangs in clusters, often a foot and a half in length, about the reefs, and 

 is one of the most gorgeous objects of coral growth. The dried specimens often closely 

 resemble Esper's figure. The colours are either white, orange, or crimson, and often the 

 polyps are crimson, when the branches are of either of the other colours. The polyps 

 are not at all retractile, and when unexpanded, the tentacles merely fall together, nearly 

 as represented by Lesson. 



FAMILY III. CORNULARID^. 

 Alcyonaria coralligena ; corallis cornets tubulatis. 

 Coralligenous Alcyonaria ; the coralla corneous, tubular. 



The CoruularidaB resemble the Xeninae in their polyps, and are 

 peculiar only in forming a corneous tube, into which the head of the 

 polyp may be withdrawn. Only a single genus has been recognised, 

 and that corresponds to the Rhizoxeniae in its mode of budding from 

 creeping filiform shoots or stolons. The genus Clavularia of Quoy 

 and Gaymard, if correctly characterized, should form a second genus 

 analogous to the Anthelise, with which the Zoantha thalassanthos of 

 Lesson, mentioned under Rhizoxenia, probably belongs. 



GENUS CORN UL ARIA. LAMARCK. 



CornularidcB corneo-coralligence, non acrogence, per stolones filiformes 

 gemmates. 



