﻿Vail : Studies in the Asclepiadaceae. 39 



Curtiss, 1886, in Herb. Gray; Titusville, A. H. Curtiss, Distr. N. 

 Am. PI. no. 2279; Manattee, J. H. Simpson, 1889; Nash. no. 

 1092, 1894; Nash. no. 1814, 1895. In all these specimens pre- 

 served in the Herbaria of Harvard University, U. S. Nat. Mus. and 

 Columbia University, the umbels are on peduncles varying from 

 1-5 cm. in length and there is no evidence of their being sub- 

 sessile. 



In the same issue of Pittonia, on page 233, Prof. Greene 

 claims that the notch of the anther-wing is an invariable char- 

 acter of Acetates, when, as a matter of fact there are species 

 with and without notched anther-wings. Those without notches 

 are Acerates lanuginosa, A. viridiflora and its two variations* 

 A. bifida and commonly A. auriculata, the latter however occa- 

 sionally with small notches, and very peculiar and nearly unique 

 anther-wings. They are very narrow, not salient at the middle > 

 but of about equal width from top to bottom, the margins ap- 

 parently flattened and meeting up the middle. The remaining 

 North American species have notched anther-wings. The notch 

 is evidently a very variable character, often so on the same plant 



Prof. Greene asserts that the inflorescence of Acerates is 

 strictly lateral. On the contrary in Acerates lanuginosa the solitary 

 umbel is always terminal. In A. Floridana, the species on which 

 the genus was based, there are occasionally a solitary or two ter- 

 minal umbels. 



