26 



The Microscope. 



differentiated into peduncle and sporange, but consists solely of 

 the latter, which then developes very few zoospores. 



Figure 1 shows two connected frustules of Pinnularia in girdle- 

 band view, with a number of sporangia attached to each. Fig* 

 2. Pinnularia frustule with separated girdle-bands. The fungus 

 has penetrated through the raphes of both valves, the course of 

 the mycelial threads being well shown. Fig. 3. A partly 

 emptied sporange with zoospores. Figs. 4-8. Development of 

 the sporange from the zoospore. 



WAYS 



ANDIAEANS 



BALSAM MOUNTS. 



EDWARD W. SHARP, PH. G. 



Canada balsam is probably more used as a mounting medium 

 for microscopical objects than all others, and yet it is apt to be 



