426 Vail : Studies in the Asclepiadaceae 



of the plants in the Michaux Herbarium proper, but are appar- 

 ently more carefully labeled and named than those in the Museum. 

 These last were annotated by Dr. Gray. The first sheet there has as 

 inscription '' Cynanchuvi inacrophyllinn capsulis angiilosis " and is ap- 

 parently the plant previously named Vincctoxicum gonocarpos Walt, 

 and the plant which Dr. Gray (Proc. Am. Acad. I2 : 75) recog- 

 nized as Gonololms lacvis var. macropliyllns. The specimen in the 

 Richard Herbarium has the name " G. Jiiacrophylhts" and habitat 

 " In si/vis Caroliniae " on the sheet and is the same plant as the one 

 in the Herb. Michaux. 



The second species, Gonolobus hirsutiis, is more difficult of de- 

 termination as of course I was not able to make a dissection of the 

 flower and the species is not so readily recognized as the first. 

 There are muricate follicles in both collections and in Herb. Rich- 

 ard two racemes, one dark purple and the other very faded, dull 

 greenish and shrunken ; the leaves are large and the plant could 

 be referred as readily to G. Carolpiensis as to G. hiisntus. It is 

 apparently identical with the plants that have been named G. hir- 

 siitiis var. flaviduliis. (See plants collected by Dr. Mellichamp at 

 Bluffton, S.C, and so named by Dr. Gray). Since seeing these types, 

 I have examined a long series of the G. Jiirsutiis and var. flavidu- 

 liis and also G. CaroUncnsis and have come to the conclusion that 

 it will take very critical study and much more material, especially 

 fresh material, to determine whether there are really two species 

 there or only one. The coronal characters are difficult to reach in 

 the dried plants and in the specimens which have passed through my 

 hands I have found every form of crenation, both regular and ir- 

 rep-ular and ereat variation in the thickness of the crown-margin 

 and also numerous instances in which the thickened alternate cre- 

 nations have a very pronounced horn-like process within. Some- 

 times these last characters showed themselves in all stages of 

 development from a faint obscure ridge near the apex of the crown- 

 segment to a sharply incurved tooth. These again were to be 

 found on one or two of the segments and again on every one of 

 them. So far as I have been able to note, these characters are 

 constant on the same plant. In some specimens the crown is 

 uniformly thin, entirely lacking the alternate thickened divisions 

 of the descriptions, others again have the thin geminate teeth 



