DESMIDIEiE. 97 



plants. In this case considerable care is required, lest the group 

 be lost by diffusion through the surrounding water. 



When the specimens are wished to be mounted for the cabinet 

 the best preservative solutions are aqueous solutions of kreosote 

 or carbolic acid. In the author's opinion, the best way is to 

 emplo}'" preservative gelatine. They are thus preserved in a 

 perfectly natural manner, without any danger of leakage, a result 

 that is so often an occurrence in the cabinets of the most careful 

 and experienced microscopists, 



"With these few observations, and the following catalogue of 

 localities, it is hoped that the members of the Society will find 

 less difficulty in their search for specimens of these wonderful and 

 incomprehensible organisms. 



Arthrodesmus convergens, (Ehr.) 



Ditches at Henbury , Yate Common ; the "Water 

 Works Reservoir, on Durdham Down. 



Arthrodesmus incus, (Breb.) 



Back of Eedland Court ; Yate ; Westbury. 



Closterium lunula, (Miiller.) 



Fields near the I^ew Passage; Cross Hands; 

 Fields near Chilney Springs; Reservoir on 

 Durdham Down. 



Closterium acerasum, (Schrank) 



Side of Railway near Patchway Station ; Ditches 

 at Shirehampton ; Aust. 



Closterium costatum, (Corda) 



Stapleton; Portskewet; Leigh; Bedminster. 



Closterium didymotocum, [var. Baillyanum,] (Breb. 

 Under Penpole. 



Closterium Ehrenbergii, (Menegh.) 

 Ashley Brook. 



Closterium Leibleinii, (Kutz.) 



Shirehampton ; Pilning ; New Passage. 



H 



