24 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



lines for a short time in some dilute acid, which, by removing the calca- 

 reous matter, renders the specimens more flexible. 



As we have said, selected material for future study should be put into 

 alcohol. Several other preserving fluids have been recommended, but 

 none in the long run do as well as alcohol. Some species do well in 

 glycerine, especially parasites like Streblonema and Bulbocoleon, which 

 grow in the fronds of other species. A one per cent, solution of osmic 

 acid is a favorite preserving fluid of some botanists. Certain sea- weeds, 

 as the PhocosiwrecE, can be mounted for the microscope in almost any 

 of the ordinary mounting fluids, and keep very well. The Floridece, on 

 the other hand, do not keep at all well, and after a few months the pre- 

 parations begin to spoil. A saturated solution of calcic chloride, a mix- 

 ture of glycerine and acetic acid, half and half, boiled and filtered, weak 

 solutions of carbolic acid, or a one per cent, solution of osmic acid are all 

 about equally good for mounting algae. As we have said, Phccosporece 

 generally do well and Floridece badly, but one sometimes has success 

 even with the latter. 



