130 



CORALS 



(lichotomous and the branches are arranged more or less in 

 one plane (Fig. 58). 



A very fine specimen obtained by the GoLiseeker ^ at 

 a depth of 183 fathoms in the Faroe Channel was nearly 



three feet in height with a 

 spread of fourteen inches. 

 But this specimen was ex- 

 ceptionally large. 



The polyps are about 

 5 mm. in length, arranged 

 densely and quite irregularly 

 on a thin coenenchym, 

 slightly curved and, as 

 observed b\' Clusius, bent 

 downwards. The polyps are 

 protected by a number of 

 large overlapping calcareous 

 scales, and the disc and 

 retracted tentacles are 

 covered by eight smaller 

 opercular scales (Fig. 59). 

 There is no record of any of 

 these polyps having been 

 observed fully expanded, so 

 that we have no knowledge 

 of their appearance except 

 in the retracted and some- 

 what contracted condition 

 in which they are seen when 

 they are brought on deck 

 from the depths of the sea. 



One of the most note- 

 worthy features of Primnoa 

 reseda is the brilliant salmon-pink colour it shows when fresh, 

 which perhaps justifies the enthusiastic comment that it is 

 " one of the most gorgeous animals within the British area." 

 The colour is, however, not permanent like the colours 

 referred to in other Alcyonaria, but dissolves in the pre- 



^ See J. A. Thomson, Proc. Roy. Soc. Edm. xvii., 1906. 



Fig. 58. — Primnoa reseda. A part of 

 a large specimen. On the left of the 

 photograph the bark has been scraped to 

 show the horny axis. Nat. size. 



