CONTRIBUTIONS TO WESTERN BOTANY NO. -IS -^^l 



Many others hold the same views. Payson is adding nothing to accepted 

 theories in this. But is the idea a true one? The annual habit is the 

 product of seasonal influences mostly cold of winter which is a recent 

 element geologically. All the primitive species of plants were perennial. 

 The annual habit is the product of the attempt of plants to adjust 

 themselves to new conditions, and in adapting themselves to them cer 

 tain organ!3 and appendages became useless and aborted. Therefore the 

 absence of certain organs is more a reversion than an evidence uf prim- 

 itiveness in annuals. The problem could be attacked in another way 

 by checking up the development of special organs in annuals. 



Are annuals specially deficient in dipsection of leaves or pilbc- 

 scence? We think not. Are they lacking in essential oil^^? Certainly not 

 in the Capparidaceae. The Cruciferae nearly all lack glandular append- 

 ages, and yet they are assumed to be derived from the Capparidacca-.' 

 family. But in all probability the reverse is the ca,^c, in spite c"f the 

 special floral characters. When we come to study the genera of Cusn- 

 ferae we find a higher development of floral characters in those gt?ne''a 

 assumed to be nearest the Capparidaceae, namely Thelypodi-jm, Stan- 

 leya, Streptanthus, Caulanthus, than in Draba, Arabis, Sisymbfiura, 

 Erysimum, many of whose species are annual, while the enumerated a-x- 

 with few exceptions annuals or biennials. It is true that Payson sa>? 

 conclusions cannot be based on small numbers of sj>ecies, but he aotM 

 ahead and does it just tlie same. Very few of us older fieldl botam^N 

 would even now have the temerity to try to explain genetic origii ^^ 

 western plants, but inexperienced young men feel competent to do it. To 

 go into details on this point would take too much .^pace here. 



(2) That a stipe is more primitive and its absence less so would 

 be 

 That the specialized genus Stanley 



very hard to prove when we consider the stipitate genera and species^ 

 at the specialized genus Stanleya is lower than Draba, Arabis, T.e>- 

 querella, etc. I do not believe, or that the still more specialized g-n-' a 

 Caulanthus, Thelj-podium, and Streptanthus are lower than they, woin<l 

 be unique. In the nature of things one is going far back to a.ssume fhfit 

 stipitate pods was the rule in primitive Sipecies, as far as he would go 

 if he assumed that pine cones to be primitive should have had definit<> 

 axes between the scales, when the probable fact is that when Ihe pine* 



originated tlie axis had already been aborted. 



(3) I fail to see any cogency in the assumption that a lorn: and 



pod 



flat one, for the rea.^nn 



that the last specialized pods are mostly short, at least not elongated, 

 and are not terete. Most of the terete pods ha 



n 



velopment of secondary ribs along the middle of the valves as is s-hoi 

 in Er>'simum, Caulanthus and Sisymbrium, which is distinctly not a 



primitive character. 



(4) Very likely Payson will say that his conclusions as to these 

 evolution factors is meant to apply only to the Sisymbrium group. In 

 rrply I would say that this throws the burden of proof all the more 

 on him. Under this head he assumes that the original species were 



