34 A MONOGRAPH OF THE 



fistulse and central cloacal cavity is abundantly furnished 

 with circular nucleated cells varying in diameter from ^th 

 inch to ~ooth inch ; they are regularly dispersed, and are 

 seldom more than about the length of their own diameter 

 distant from each other. The nuclei occupy from one 

 third to about two thirds of the diameter of the interior of 

 the cell, and neither in it nor in the cell surrounding it is 

 there any appearance of granules. I could not detect any 

 of these cells in the dried specimen of the same species for 

 which I am indebted to my friend Mr. Bean, nor have I 

 ever seen similar cells in any other calcareous sponge. It 

 is difficult in the present limited state of our knowledge of 

 this tribe of sponges to determine the office of these bodies 

 in the economy of the sponge, but it is most probable that 

 they are the reproductive organs. 



4. Leucosolenia coriacea, Bowerbank. 



Gkantia coriacea, Fleming. 

 Johnston. 



Sponge. Sessile incrusting; fistulas tortuous, anasto- 

 mosing ; surface smooth, parieties thin. Cloacal 

 cavity continuous, unarmed internally ; mouths incon- 

 spicuous. Oscula and pores inconspicuous. Spicula 

 of skeleton equiangular triradiate, radii thick, apices 

 obtusely pointed. 



Colour. Dark crimson, Mrs. Buckland ; dirty bluish 

 gray or white, Johnston ; lemon yellow, Rev. A. M. Norman ; 

 deep nut brown, J. S. Bowerbank. 



Habited. Scarborough, Mr. Bean ; Peterhead, Mr. 

 Peach ; Guernsey, Mrs. Buckland ; Berwick Bay, Johnston ; 

 Guliot Cave, J. S. Bowerbank; Burra-Firth Cave, Rev. 

 A. M. Norman-. 



I found this sponge by the aid of my friend Mr. Bean of 

 Scarborough, and I have also received it from him in the 



