- 89 



twisted like a screw and with several rows of long many- 

 pronged bristles spread out in every direction and quite stiff 

 when ripe. The fruit thus appears as a kernel set in the 

 midst of a globular transparent meshwork, the diameter of 

 the whole being 2 3 cm. (See fig. 28). These fruits are exceed- 

 ingly mobile and roll away at the slightest breath of wind. 



The fruit of Eremosparton is a one-seeded woolly-haired 

 pod, one centimetre long. The red blossoms open in May 

 or June and form small racemes, but only the earlier blos- 

 soms set fruit as the later ones are shrivelled up by 

 the heat. 



Saxaul or Sasak (Haloxylon Ammodendron) (fig. 14) only 

 thrives well where the sand has a subsoil of clay or limestone. 

 Under favourable conditions it may become a tree of 7 metres. 

 Often, however, it is a much-branched shrub. As the growth 

 is slow, this species does not stand sand-drift very well, and 

 the young, soft, leafless shoots are also bruised and damaged 

 by the sand-grains 1 ). 



These switch trees and bushes have the following cha- 

 racters in common (other details of morphology and internal 

 structure are given in chap. 13). They are small trees or 

 bushes; the Sand -Acacia and Saxaul occasionally become 

 larger trees (8 metres). 



All of them have their leaves much reduced. Ammoden- 

 dron has flat leaves, but they are small and thickly coated 

 with silky hairs. The Salsola species have cylindrical cheno- 

 podiaceous leaves with central water-tissue. In Calligonum, 

 Eremosparton and Haloxijlon the leaves are reduced to small 

 scales, and the assimilatory functions are performed by the 

 stems alone. 



The first-year shoots are frequently branched, sometimes 



*) Saxaul is said to form vast bushlands ("forest", comp. LIPSKY above 

 p. 28) east of Lake Aral (Wladimirskaja). The trees here are said to attain 

 a height of 1618 feet and have a thick tap-root. Saxaul often occurs here 

 together with rushes and is supposed to stand in a certain relation to the 

 Syr Darya (Jaxartes) inundation area. "The Saxaul forests everywhere begin as 

 a low thorny scrub along with Tamarisks, then they become bushlands and 

 finally forests." (MIDDENDORFF p. 308). LIPSKY (1911 p. 14) denies that the 

 growth of Saxaul is necessarily slow. 



