196 



BIOLOGICAL LECTURES. 



deflexed stalks, some erect and recently pollinated, others con- 

 siderably elongated and maturing fruit. Both specimens were 

 dug up surrounded by a large mass of soil. They were washed 

 clean under a strong water jet. The dense coralloid mass of 



humus or saprophytic roots 

 was thus exposed (Fig. 2). 

 One of the sickly looking 

 masses was at once dropped 

 into an alcohol jar ; the 

 other was boiled in water for 

 ten minutes, allowed to dry 

 slightly, and thereafter 

 placed in alcohol. The for- 

 mer is now black and un- 

 sightly. Owing to changes 

 in the tannin cells through 

 boiling, the latter has re- 

 tained its pure, white ap- 

 pearance. 



Root parasites, again, like 

 Gerardia, Comandra, etc., 

 should be similarly dug up 

 and treated in the labora- 

 tory. As the soil is washed 

 away by the strong water 

 jet, the root-suckers of the 

 parasite are exposed singly 

 or in clusters attached to 

 the host-root. Much more 

 might be said on the sper- 

 maphytes or seed - plants, 

 but the "cryptogams" claim 

 a fair share of attention, and 

 can yield fine results. A 

 series of specimens placed side by side to illustrate the oophyte, 

 and stages in the developing sporophyteof our common Hair-moss 

 {Polytrichtim commune), forms a natural picture that excels the 

 best diagram or model. These can either be arranged in jars in 



Fig. 2. 



