19 



Page ii S. virescens, Morel, is 

 considered a var. of debilis 

 and the name vitrea is pre- 

 occupied by Pfeiffer, so our 

 British species should stand 



S. virescens, Jeff, non Morel. 



= vitrea, Jeff, non Pfr. 



unless Baudon's reference of it to 

 S. Stagnalis, Gass. be accepted. 



add 



c. jeffreysi, Baud. 



Page 12 add 



Limncea glutinosa 

 var. d. albida, Wilms. 



Page 13 add 

 L. stagnalis 



var. r. expansilabris, Mart. 



Page 15 — add 



H. jenkinsi, 



c. ecarinata, Jenkins. 



and remove — 



ovata, Jeff to No. 128 as 

 H. ventrosa, 



f. ovata, Jeff. 



CORRIGENDA. 



Page 2 for Fairway read Fairfax. 



Page 15 for B. tentaculata var. rnfescens read var. rufescens. 



