290 PRACTICAL HISTOLOGY [XXXVI 



irrigated with inethyl-green in 1 p.c. acetic acid. The same 

 stain may be used for other fresh tissue cells, or for fresh ova. 



Plant tissues. The rootlets of pine may be obtained from the 

 young plants which grow under fir trees ; it is best to dig them 

 up on a warm day, and preserve at once. Rootlets serving the 

 same purpose may be obtained by placing onions in water, and 

 keeping at about 25 C. The tips of the rootlets are cut off and 

 hardened in any of the ways given above, or in absolute alcohol. 



The anthers of a lily may be taken to show division in nuclei 

 containing a considerable amount of chromatin ; the anthers of 

 Fritillaria persica to show division in nuclei with comparatively 

 little chromatin. 



