113 



rarely exceeds a height of 2 (2, 5) metres; Alhagi Camelorum 

 and Lycinm turcomanicum, shrubs attaining a height of up 

 to 2 metres; Halostachys caspica a migrant from the desert, 

 which on the river-banks is exceedingly luxuriant in growth, 

 and amongst Tamarix bushes it may attain a height of 3 

 metres; also Equisetnm ramosissimum, Zygophyllum Eichwaldii, 

 and several casual visitors, e. g. Launaea nudicaulis, Mulgedium 

 tataricum, Plantago major. Phragmites, although strictly be- 

 longing to moister places, may also be found here; so also 

 with Calamagrostis pseudophragmites a metre-high grass with 

 thin subterranean runners, and Typha LaxmannL 



These plants form low thickets as represented in fig. 19. 

 They present a particularly curly or rufled appearance, because 

 the bushes appear devoid of leaves; nothing is seen but twigs 

 forming a confused mass, and where (as in the picture) Ly- 

 cinm and Alhagi are prominent the thicket is almost impene- 

 trable on account of thorns. The scattered Erianthus-iussocks 

 with their orderly ranks of flowering shoots and long leaves 

 are an agreeable relief in this otherwise confused picture. 



In other places the thorny species disappear and the vege- 

 tation is formed by Tamarisks, Glycyrrhiza and grasses. Some- 

 times these also occur: Elceagnus hortensis var. continentalis, 

 bush-willows and poplars. (Salix angustifolia var carmanica, 

 S. Wilhelmsiana, Populus pruinosa, P. euphratica). 



These, especially the poplars, generally attain their full 

 development at higher elevations. Populus pruinosa is the one 

 I have seen most frequently but P. euphratica is also wide- 

 spread. I saw it frequently in the country round Chiwa. Both 

 occur either as shrubs or as trees up to a height of 6 8 

 metres, and are noteworthy because of the wide variations in 

 shape presented by their leaves as illustrated in fig. 20. The 

 narrow leaves are mostly found on bushes which may be 

 entirely narrow leaved or somewhat broader leaves may occur 

 higher up the branches. Larger trees, during the flowering 

 period or after it, generally have broader leaves. Through a 

 twisting of the petiole, the leaves assume a vertical edgewise 

 position and they have a light greyish colour. 



These species of poplar may occur as shrubs interspersed 

 amongst Tamarisks, Halimodendron, Erianthus, etc., but they 



