502 ALCYONIDIID^E. 



having no septa visible on the surface, and by its large 

 papillae, marking the entrance of the cells. The ova 

 also appear to be distributed singly throughout the 

 zoarium, instead of being produced in clusters. Joliet"^ 

 states that it occurs under two very different forms : in 

 its young state it consists of a very delicate transparent 

 crust ; but with age it increases in thickness, and forms at 

 last a fleshy mass which covers the Fuci so as completely 

 to distort them, and even throws out occasional lobes. 

 In this condition it has a spongy appearance, and is of a 

 dull grey colour. In the months of May and June, he 

 adds, the ova are developed in immense numbers, and 

 appear as white, or occasionally rose-coloured, points scat- 

 tered over the surface of the colony. 



The species requires further investigation. 



b. Zoarium argillaceous. 



Alcyonidium parasiticum, Fleming. 



Plate LXIX. figs. 4-6. 



Alcyonium parasiticum, Flem. B. A. 518: Blainv. Actinol. 525. 

 Alcyonidium parasiticum, Johist. B. Z. ed. 2, 362, pi. Ixviii. figs. 4, 5 : 



Hassall, Ann. N. H. tii. 370 : Bcid, Ann. N. H. xtI. 393, 



pi. xii. fig. 11 : Van Ben. {Halodacti/lus) Eech. (Mem. 



Bruxelles, xviii.), 62, pi. viii. figs. 9-12 : BaJi/eU, Eem. An. 



ii. 33, pi. X. : Smitt, loc. cit. 498 and 514, pi. xii. figs. 14-19, 



&c. 



Zoarium incrusting, argillaceous. Zocecia very small, 

 with minute papillae disposed round an oval or circular 

 area, which is covered by a smooth hyaline membrane. 



Polypide with 15-16 tentacles. 



* ' Bryozoaires des cotes de France,' 1877, p. 100. 



