192 



The leaves are bipinnate with about 10 leaflets on each 

 pinna, these are 3 9 mm. long, oblique, hairy and when 

 the sun shines they are directed upwards. Older branches 

 have white bark and are covered with prickles. 



The year-shoot is branched. During the same year each 

 axil gives off either an inflorescence or a branch, or two bran- 

 ches, or a branch and an inflorescence. The 

 longest year-shoot branches are about 15 

 centimetres long at the beginning of June 

 and only the outermost 2 centimetres are not 

 fully lignified. The year-shoot branches bear 

 many leaves which often subtend inflores- 

 cences, but apparently no new branches. 

 The year-shoot branches cannot be termed 

 assimilating shoots as they are persistent. 

 Prosopis flowers from May to July. The 

 inflorescences are long racemes with small 

 flowers. The fruit is a fleshy pod 3 4 

 centimetres long. 



The leaf is isolateral in structure (fig. 

 37). The epidermis contains tannin and 

 has stomata on both surfaces; 6 7 layers 

 of palisade cells fill up the whole leaf. 

 The veins have bast sheaths on both sides. "Speichertrach- 

 ei'den" are present. 



Fig. 37. Prosopis 

 Stephaniana. Sec- 

 tion through the 

 leaf. X 230. 



Zollikoferia acanthodes Bois. 



is^ said to be a stunted thorny shrub with forked angular 

 branches and with thorn-like short-shoots. A few ovate or 

 oblong leaves occupy the base of the branches, they are 

 thickly coated with white spines and soon fall off. (From 

 BOISSIER fl. orientalis.) 



Atraphaxis spinosa L. 



A strongly branched shrub never exceeding a height of 

 one metre. The leaves are shortly petiolate, circular-ovate, 

 rather thick and about one centimetre long. The bark is 



