THE KANSAS UNIVERSITY 

 SCIENCE BULLETIN. 



VOL. IX, No. 19.] SEPTEMBER, 1915. [ v 1 ho xi e x s n r o ie i S 9 



Histology of Malva rotundifolia. 



GRACE McCRONE. 

 Plates LIV-LIX. 



71 /f ALVA ROTUNDIFOLIA is a low-growing mallow com- 

 1VJ. mon in this section of the country, and generally grow- 

 ing as scattered individuals or small groups, but sometimes oc- 

 curring in large patches. It begins growth early in spring and 

 lasts until very late in autumn. 



The material used for this investigation was obtained on the 

 University campus. The standard histological methods were 

 employed, and the illustrations were made from permanent 

 slides stained with safranin and hematoxylin and from free- 

 hand sections otherwise treated. Microchemical tests were 

 used on both free-hand and microtome sections. Some of the 

 drawings were made by use of the camera lucida on the micro- 

 scope and some with the projectoscope. 



STEM. 



The main stem branches perfusely close to the ground. The 

 branches start up in a vertical direction, but as they become 

 numerous the older branches lie prostrate on the ground for 

 a greater part of their length. This position has a noticeable 

 effect on the tissues of the stem, there being less bast fiber 

 tissue on the lower than on the upper side, and in the starch 

 sheath there is more starch in the side near the ground. The 

 branches are about two or two and one-half feet long. 



Received for publication June 10, 1915. 



(261) 



