440 



the majority oC tlie species wliich he has examined had the 

 stomata most numerous upon the upper surface. 



All the species of JiatiHnrulus, lidtravhiuni confervoldes 

 and Anetnone Richardsoni were furnished with hydathodes 

 and ep it lie mala at their leaf-apices. It is usual for the water- 

 pores to occur marginally upon a somewhat upwardly-directed 

 surface, and in all these species the epithema is essentially 

 similar in structure ; the tracheids are somewhat spreading and 

 terminate at the intercellular spaces, and the cells of the me- 

 sophyll are shortly branched and have strongly undulating walls. 

 Chlorophyll is usually absent from the epithema and the nuclei 

 of the cells were remarkably large. 



From the consideration of the above it will be seen that 

 the species which have been investigated are very similar in 

 regard to the greater part of their structure; and, as is natural, 

 the similarity is especially conspicuous in the relatively nume- 

 rous species of Ranunculus^ it has also been shown that in 

 the material at hand no considerable differences have been able 

 to be demonstrated in the individuals of the same species from 

 different regions (see however R. acer and R. affinis). 



27— 6— 1911. 



