280 ANATOMY AND PHYSIOLOGY 



Fig. 



317. An ovarramof SponffiUafluviatilism its natural state, 



exhibiting the foramen. X 83 linear. Page 

 132. 



318. A perfect skeleton of an ovarium of SpmgiUa fiuvia- 



tilis, Johnston, prepared with nitric acid. X 183 

 linear. Pages 60 and 136. 



319. View of a section, at right angles to the surface, of a 



fragment of the skeleton of the ovarium of Spon- 

 ffilla fluviatilis, prepared with nitric acid, exhibiting 

 the relative positions of the spicula in the skeleton. 

 {a) A spiculum detached from the same ovarium 

 X 308 linear. Pages 60 and 136. 



320. A skeleton of an ovarium of Spongilla lacmtris, pre- 



pared with nitric acid, exhibiting the spicula in 

 situ and the foramen. X 183 linear. Pages 58, 

 60 and 137. 



321. Two of the reticulated cases of the ovaria of Spongilla 



Brownii, Bowerbank : — a, an empty case ; b, a 

 case containing the skeleton of an ovarium. X 50 

 linear. Page 139. 



3 "2 2. A reticulated case of an ovarium of SpongiUa reticu- 

 lata, Bowerbank. X 175 linear. Page 138. 



323. Skeleton of an ovarium of Sponpitla reticulata, 



Bowerbank, without its case, prepared With nitric 

 acid. X 175 linear. Page 138. 



324. A perfect ovarium of Diplodemia vesicula, Bower- 



bank, and a portion of a second one, showing the 

 interior and the thickness of its walls in its 

 natural state. X 83 linear. Pages 60 and 140. 



325. An ovarium of Geodia McAndrewii, Bowerbank, MS., 



in very nearly an adult state, showing the struc- 

 ture and position of the conical foramen for the 

 discharge of the ova, natural condition. X 183 

 linear. Page 142. 



