No 437-] 



X( ) EES AXD LITER A El RE. 



355 



Aroideae, Palmes and Scitamineae, of the monocotyledons and the 

 Ranunculaeeae of the dicotyledons. In the third part she takes up 

 general considerations on the origin of the monocotyledons. 



In the space of a review, it is necessarily impossible to state in 

 detail the evidence presented, but some of the main points of argu- 

 ment may be given. As in her previous paper she affirms her belief 

 in the real systematic value of some of the vascular characters of the 

 young seedling — at least of the Liliaceae — and emphasizes the 

 structural similarity of some of the Ranunculaceous seedlings to those 

 of certain forms which she concludes represent the primative type of 

 vascular arrangement in the Liliacea-. She expresses her belief in 

 the genetic connection of Eranthis and Anemarrhena, but even if 



Eranthis may illustrate the double origin of the Anemarrhena coty- 

 ledon. Two tables are given, one listing clicotylodenous seedlings 

 with a well-marked cotyledonarv tube and the others those in which 

 the union of the cotyledons occurs along one margin only. The 

 ecological relations of these seedlings are discussed in relation to 

 their bearing upon the development of a permanent monocotyled- 

 onous type, and it is found that almost all belong to plants of 

 geophilous habit and that in some cases the whole structure remains 

 under ground during the first year of their growth, developing under- 

 ground organs for the tiding over of the unfavorable vegetative period 

 to follow. Such considerations have led her to regard the monocoty- 

 ledon as an organism adapted primarily to a geophilous habit, and 

 she thinks that when considered from this point of view many 

 puzzling details of structure in the monocotyledons become compre- 

 hensible. A brief discussion of some of these points is given. A 

 bibliography of forty-five titles lists the literature to which reference 

 is made. 



While the presentation of the theory is confident, it is not without 

 due reserve. " The evidence is obviously incomplete. The theory 

 itself cannot be considered as proved in any sense. It is brought 

 forward as a working hypothesis which I have found in practice to 

 be suggestive and illuminating." The favorable tone of the present 

 review may be attributed to the desire of the reviewer to present the 

 theory from the point of view of the one who proposes it, but no one 

 will deny that the data presented in the paper is of the greatest value 

 and that the theoretical considerations will receive the careful attention 

 of botanists and be of importance in the elucidation of the great 



