5 70 MONTGOMER Y. 



EXPLANATION OF PLATE XXIV. 



Figs. 137-139. Germinal vesicles of Tetrastemma catenulatum, the nucleoli 

 omitted in Fig. 139 (aq. sol. sublimate; Del. haematoxylin, 25 min. ; eosin, 5 

 niin.). 



Figs. 140-1 j8 : Egg development of Amphiporus glulinosus. 



Figs. 140-143. Germinal vesicles (aq. sol. sublimate ; Del. haematoxylin, 20 

 min. ; eosin, 5 min.). 



Figs. 144-146. Germinal vesicles with surrounding cytoplasm (as in 143). 



Figs. 147-150. Germinal vesicles (as in 143). 



Fig. 151. An abnormally large yolk ball (aq. sol. sublimate; aq. sol. dahlia, 

 15 min.; eosin, 5 min.). 



Figs. 152-154. Germinal vesicles (aq. sol. sublimate; haematoxylin, 45 

 min. ; ferro-ammonio-sulphate, 45 min. ; haematoxylin, 45 min.). 



Fig. 155. Ovum and a part of the gonadal cavity in which yolk balls lie, only 

 a portion of the cytoplasm drawn (as in 1 52). 



Figs. 156-158. Germinal vesicles (as in 154). 



Figs, i^g-tyy : Egg development of Lineus gesserensis. 



Fig. 159. Nuclei from which the germinal vesicles are derived, from the cyto- 

 plasm of the gonad (Hermann's fluid ; safranin, 70 hrs.; gentian violet, i hr. ; 

 orange G., 2 min.). 



Fig. 160. Ovum (as in 159). 



Figs. 161 and 162. Germinal vesicles (as in 159). 



Fig. 163. Group of neighboring nuclei from a gonad, showing mitotic stages 

 (aq. sol. sublimate ; Del. haematoxyhn, 20 min. ; eosin, 5 min.). 



Figs. 164-172. Nuclei from gonads (as in 163). 



Figs. 173-176. Germinal vesicles (as in 163). 



Fig. 177. The largest ovum found, only a part of the cytoplasm drawn (as in 

 ■63)- 



