152 MEMBRANIPORID^E. 



LOCALITIES. Antrim (Hyndman) : off Donaghadee, 32 

 fathoms (Mr. W. Swanston) ; Guernsey ; off the Deadman, 

 Cornwall, GO fathoms ; South Devon (T. H.) : Birterbuy 

 Bay (A. M. N.). 



The massive, often subclavate, spines and the avicula- 

 rium, which is of the Flustrine type, distinguish this fine 

 species from the other Membraniporce. The avicularium 

 is always placed, as amongst the Flustrte, immediately 

 above the zooecium, an a distinct area, which is in a 

 line with the cells. We have a similar form in M. corni- 

 gera. Through the present species and such a form as 

 Flustra denticulata, Busk, a very close relationship is 

 established between the families of the Flustridae and 

 Membraniporida. 



MEMBHANIPORA DISCRETA, Hincks. 

 Plate XIX. figs. 8, 9. 



MEMBKANIPURA DISCRETA, Hincks, Devon & Cornw. Cat., Ann. N. H. ser. 3, 

 ix. 200, pi. xii. fig. 1 (page 40, sep.). 



Zocecia ovate, separate, varying in size, and irregularly 

 disposed ; the margin cut into about twenty lobes, sup- 

 porting as many delicate, sharply pointed spines, \vhich 

 bend slightly inwards. Ooecia very small, globose, 

 frosted. 



In the only two specimens I have seen, the colonies con- 

 sist of very minute and inconspicuous groups of cells. 



HABITAT. Shells from moderately deep water. 

 LOCALITIES. South Devon; Guernsey (T. H.). 



I do not identify the present species with Smitt's M. 

 lineata, forma discreta, which, so far as I can judge from 



