154 THE PLANT WORLD 



Throughout this treatise Prof. Goebel continually em- 

 phasizes the prime fact, that teleological and adaptational 

 "explanations" of these phenomena are worse than valueless 

 because they are misleading. Wherever a purpose is apparent 

 in the reactions of the plant this exists only subjectively in 

 the mind of the observer. The plant merely "does that 

 which, under definite conditions, it must do." 



Munich, April 20, 1908. 



By B. E. Livingston. 



SOME SEEDLINGS OF THE DESERT. 



Two of the most common desert plants of the mesa 

 central Mexico are the sotol {Dcisylirio)i sp.) and the 

 Palma loca (Yiucd filifcra). Fheir seedlings, as is usual 

 in the case of desert plants, are seldom met with, either on 

 account of their small number, or because of the necessity 

 of diligent search in order to find them. When found they 

 frequently present points of interest at variance with the 

 mature plants. For this reason the following notes are 

 given, 



Sotol. — The chief features of the seedling of this plant 

 worthy of especial note are the contractile roots, found in 

 a probably great number of monocotyledons, and the leaf 

 arrangement. The compact character of the soil in which 

 the sotol grows, dry and rocky as it is, would hardly give 

 grounds for expecting this type of root, the degree of effect- 

 iveness of which would be interesting to know. The stem of 

 the seedling is somewhat bulbous, after the fashion of an 

 onion, but laterally compressed, and the leaves are arranged 

 in two vertical rows, a phyllotaxy which becomes very mark- 

 edly changed as the plant matures. The leaves in the 

 plantlet in question are about 50 cm. long. Its age is un- 

 known. 



