PLATE XLIV. 109 



rocks between high and low water mark, in the neigh- 

 bourhood of Hastings, although it is by no means un- 

 common in such localities at Tenby. It is of very 

 common occurrence among the sponges brought in 

 from the Diamond Ground, by the Hastings trawlers, 

 and some of the specimens exceed the figured one in 

 size. 



From a more extensive acquaintance with this species 

 it appears almost to rival Halichondria panicea in the 

 variety of forms it assumes. I have it parasitical on 

 small branching fuci, embracing the stem, and forming 

 with them an irregular mass, thinly coating the valves 

 of Pecten opercularis, in small thick masses on the 

 Tenby Rocks between tide marks, and in irregularly- 

 shaped masses, without any indications of an attach- 

 ment, having apparently been floating freely about in 

 the sea. 



HALICHONDRIA CANDIDA, Bowerbank. 



Vol. ii, p. 251, ' Mon. Brit. Spongiadse.' 



Fig. 13. Represents the finest and best developed 

 specimen of the species. In the cabinet of the Rev. A. 

 M. Norman. Natural size. 



Fig. 14. One of the dermal spicula. X 250 linear. 



Fig. 15. A contort, bihamate, retentive spiculum, 

 from the dermal membrane. X 530 linear. 



Fig. 16. One of the skeleton spicula. X 250 

 linear. 



HALICHONDEIA IRREGULARIS, BowerbanJc. 



Vol. ii, p. 251, ' Mon. Brit. Spongiadse.' 



Fig. 17. Represents the type-specimen in the dried 

 state, and of the natural size. 



Fig. 18. One of the sub-fusiformi acerate spicula, 

 from the dermal membrane. X 250 linear. 



