110 BRITISH SPONGIADJE. 



are of very rare occurrence. A very few inequi-pal- 

 xnato-ancliorate spicula were detected among the 

 spicula separated by boiling in nitric acid, but I could 

 not detect them in situ ; they are remarkable in their 

 form, though very minute, the palmate portion being 

 quite half the length of the spiculum." 



27. HALICHONDEIA INCRUSTANS, Esper, n, 249 ; in, 108, 



PI. XLIV, figs. 712. 



1867 Dendoryx incrustans, Gray. Proc. Zool. Soc., p. 535. 

 1874 Halichondria incrustans, Carter. Ann. Nat. Hist., ser. 4, 

 vol. xiv, pp. 2 -4. 



Habitat. Budleigh-Salterton, Carter. Birterbuy 

 Bay, Galway ; Jersey ; Guernsey ; Polperro, Corn- 

 wall (N.). It is essentially a low- water-mark species, 

 generally distributed round our coast. 



28. HALICHONDRIA CANDIDA, Bow., n, 251 ; in, PI. 



XLIV, figs. 1316. 



1867 Biemma Candida, Gray. Proc. Zool. Soc., p. 539. 



29. HALICHONDRIA IRREGULARIS, Bow., n, 252; m, PI. 



XLIV, figs. 1721. 



1867 Dendoryx irregularis, Gray. Proc. Zool. Soc., p. 536. 



30. HALICHONDRIA DICKIEI, Bow., n, 253 ; in, PI. XL V 



figs. 1 6. 



1867 Dendoryx Dickiei, Gray. Proc. Zool. Soc., p. 536. 



Habitat. On Cellepora cervicornis, deep water, 

 Shetland Seas, 1863; Polperro (N.). 



