116 BRITISH SPONGIADJE. 



5. ISODICTYA FEKULA, _Z?0/y.,n. sp., IV, PI. VIII, figS. 1 3. 



"Sponge battledore - shaped, coating, adhering 

 throughout its whole length. Surface smooth. Oscula 

 dispersed, simple, minute. Pores inconspicuous. Der- 

 mal membrane pellucid, aspiculous. Skeleton having 

 primary and secondary lines unispiculous ; spicula 

 acerate. Interstitial spaces one spiculuni wide, very 

 regular. Interstitial membrane aspiculous. 



" Colour. In the dried state, dull ochreous yellow. 



" Habitat Birterbuy Bay, Ireland, 10 or 11 fathoms ; 

 Rev. A. M. Norman. 



" Examined. In the dried state. 



" Among the specimens of sponges dredged by the 

 Rev. A. M. Norman off the western coast of Ireland, 

 there was the gibbous half of a shell of Pecten mazimus, 

 thinly coated both within and without with Rajjhyrus 

 Griffitlisii, and on the surface of this species, on the 

 inner surface of the shell, were several parasitical 

 sponges, and among them two specimens of the species 

 in course of description within an inch of each other, 

 closely adhering for the whole of their length. They 

 were partially embedded in a thin broad specimen of 

 Isodictya Bowerbanki. 



<( The oval body of the largest specimen is six lines in 

 length and three in breadth, and its greatest thickness 

 does not exceed one line. The caudal appendage is 

 seven lines in length and one in breadth, so that the 

 total length slightly exceeds one inch. The smallest 

 of the two specimens has the body rather more ob- 

 tusely oval than the larger one, the length being four 

 lines and the greatest breadth three lines. A portion of 

 the caudal appendage has been lost, and half only of 



