240 UNIVERSITY OF COLORADO STUDIES 



alcoholic material of plants belonging to other families is on hand at 

 the present time and a report on a study of it will be ready in a 

 few months. 



Species exmnined. In the species selected for study the coty- 

 ledons are always epigean. They are not greatly thickened for stor- 

 age purposes and they remain active for some time after appearing 

 above ground. They all increase in size more or less and assume the 

 appearance of foliage leaves, but they are different in shape from the 

 true foliage leaves. Although sessile in most species, in some there 

 are distinct stalks which become elongated with increase in age. 

 The following species were studied : Astragalus adsurgens Pall., 

 A. carolinianus Linn., A. crassicarpus Nutt., A.fiexuosus (Hook.) 

 DouGL., A. liypoglottis Linn., A. racemosus Pursh, Aragallus de- 

 flexus (D. C.) Heller, Aragallus spicatus (Hook.) Rydb., Tri- 

 foliurn dasyphylluin Tore, and Gray, Robinia pseudacacia Linn. 

 Amorpha canescens Pursh, Lupinus pusillus Pursh, Glycyrrhiza 

 lepidota Pursh, Psoralea Kypogaea Nutt., Hedysaruin mackemii 

 Richards, and Petalostemon candidus Michx. 



External Morphology of Cotyledons and Leaves. It has been 

 frequently shown '^•^•^'> that no general relation can be established be- 

 tween the shapes of cotyledons and foliage leaves. It will not, 

 therefore, be useful to ^ive an extended account of the differences 

 noted. The cotyledons of the plants studied are ovate or oblong, 

 generally sessile or nearly so, and in most cases somewhat asymmet- 

 rical and slightly thicker than the foliage leaves. They increase in 

 size after emerging from the seed coat, usually growing to twice or 

 three times their former length and breadth. The foliao-e leaves are 

 always eventually compound but usually the lirst two or more leaves 

 are simple and frequently the succeeding ones have fewer leaflets 

 than the characteristic leaves produced by the adult plant. Lupinus 

 pusillus forms an exception to the rule as its first leaves are palmate. 



(1) Lubbock. On Seedlingrs. 1: 9. 1892. 



(2) Klebs. Beltrage zur Morph. und Biol, der Keimung. Pfeffer's Untersuchungren aus 



dem Hot. Inst, zu Tubingen. 1: 536. 1885. 

 {') Ramaley. Seedlings of Certain Woody Plants. Minn. Hot. Stud. 2: 84. 1899. 



