Bryophytes Hepaticae 215 



phyte is even more difficult to orient than that of Riccia natans. 

 Cut a slice 1 or 2 mm. thick, so as to orient the visible portion of 

 the sporophyte, and trust to luck for the orientation of the foot. 

 For studies like A and B, chromo-acetic material cut 10 n thick 

 and stained in DelafiekTs haematoxylin is very good. The starch 

 grains in the chloroplasts take a beautiful violet color with the 

 safranin, gentian-violet, orange combination. With so many stages in 

 a single section, it will be impossible to stain all of them well. A stain 

 which will show the mother cells and their divisions will be too 

 deep for the mature spores, and a stain which shows the spores 

 well will be too faint for the mother cells. It is better to stain some 

 preparations for one feature and others for another. It is not worth 

 while to steer a median course. 



