35° 



PLANT LIFE. 



growing from special parts of the surface, which are regularly 

 eaten by tlie ants and grow again, so that a constant supply is 

 at liand ; (f) dwellings of various sorts. Certain jjlants have 

 the stems hollow throughout, with special modificaLion of the 

 structure at certain spots, so that an entrance to these hollows 

 may be readily made (fig. 393). In others, ]iortions of the 

 internodes are much enlarged and hollow ; sometimes only 

 the internodes in the region of the flower clusters are thus 

 transformed. In other plants chambers arc produced by the 

 bladdery enlargement of the under part of the leaf near the 

 midrib (fig. 394). In some acacias the stipules are developed 

 as massive thorns, uhich the ants inhabit. 



475. Domatia. — Somewhat sim- 

 ilar dwelling places, though less 

 <s^— H — SSJlS'f- 1^1 1''^ perfect, are provided by many 



plants for the mites. These dwell- 



FiG. 394. 



tie. 3.,4. -Under side of the base ,,l the leal blade ,jf /-.v,;,,, /.7«t- />//,; showin? 



bladder on each side of midrib, eacli with entrance at ,i. ,i . Natural size V'l— After 



Schumann. 

 Fig. 395.— Domatia on under side of leaves. A. between midrib and laterals of 



Jsy,-h,itr!,i H, between midrib and lateral of the linden I /V//,, J-:„,of>u-a) Masni- 



fied about 5 diam, — After Lund.striim. 



ing places are in the form of minute shelters usuall\' upon the 

 under side of the leaves. They are generally formed by hairs 

 roofing over an angle of the \eins, or by various outgrowths, 

 folds and pits (fig. 395). Their significance is not at all 

 clear. 



