380 BRITISH SPOXOIAD.E. 



11. DESMACIDON JEOAGROPHILUS (Scouler, MS.), ii, 352, 

 T, PI. XIII, fig. 264; TTT, PL LXIII, figs. 814 ; 

 PI. LXXXIII, fig. 23. 



1SG7 Mgagrophila varians, Gray. Proc. Zool. Soc., p. 533. 

 IS70 Esperia (sgagropliilo, Schmidt. Spoug. Atlant., p. 77 



" Among the sponges sent to me for examination by 

 the Rev. A. M. Norman there was a specimen of Des- 

 macidon cegagropihis labelled ' Ticlemarks, Birterbuy 

 Bay.' It was of an irregular form, two and a half 

 inches long by two inches at the greatest width, but it 

 did not exceed half an inch at its greatest thickness. 

 It was of a dull cream-yellow colour, and its upper 

 surface was abundantly corrugated or minutely papil- 

 lated, and the general aspect was that of a very 

 characteristic specimen of the species. On taking 

 sections at right angles to the surface from the 

 thickest end of the sponge, and a portion from the 

 dermal surface, and mounting them as usual in Canada 

 balsam, and examining them with a power of 200 

 linear, they presented a most anomalous appearance. 

 In addition to the usual strong spiculo-fibrous skeleton 

 of the Desmacidon, there were several detached fasciculi 

 of skeleton spicula, and a considerable number of 

 rosette-shaped groups of inequi-palmato anchorate 

 retentive spicula ; and I at once saw that I had before 

 me the elements of two very distinct genera of species, 

 Desmacidon cerjagropilus and Rapliiodesma lingua inter- 

 mixed and so incorporated as to completely simulate a 

 single individual of a most extraordinary structure. 

 I carefully examined the sponge with a lens of two 

 inches focus, but I could not discriminate the two 

 discrepant tissues ; but on taking sections and a portion 



