﻿Vail : Studies in the Asclepiadaceae 179 



notated by Dr. Torrey, should be numbered 1078a. A speci- 

 men from this collection in the Herbarium of the U. S. Nat. 

 Museum answers the description very well, but lacks any kind of 

 a number so I do not like to refer to it with certainty. The first 

 number of Wright's (1685), is undoubtedly the same as Hartweg's 

 plant and is A. galioidcs, H.B.K.; but the no. 1686 seems to show 

 a marked variation which is rather striking. The same plant 

 occurs is Wright's Western Texas collection and more recently 

 has been found at Fort Verde, Arizona. 



A low (2-3 dm. high), slender plant, with remarkably crowded, 

 long, narrowly linear leaves which are verticillate in fours or the 

 uppermost in twos or threes. The internodes at the base of the 

 stem are only from 6-10 mm. long and the leaf-scars are con- 

 spicuous, a character which I have not noticed on any other forms. 

 I have little doubt but that this is a good species and give it the 

 name of Asclepias subverticillata as it is included in Dr. Gray's 

 variety. 



5. Asclepias linearis Scheele, Linnaea, 21: 758. 1848. 



Glabrous except the minutely pubescent stems and pedicels. 

 Stems terete, angulate above, 2—5 dm. high, from a rather slender, 

 short rootstock, covered with few ligneous ? rootlets, simple or 

 branched near the base, minutely pubescent, commonly in lines 

 above : leaves narrowly linear, 4-8 or 10 cm. long, 1-3 mm. 

 wide, elongated, acute, glabrous or with few scattered hairs, 

 1— nerved, the veins obsolete, coriaceous, margins revolute : pe- 

 duncles longer than the 1 cm. long, filiform, minutely puberulous 

 pedicels, but much shorter than the leaves : umbels 3-8, all lateral, 

 1.5-2.5 cm. in diameter, few to several-flowered; column slender, 

 conspicuous : corolla-segments greenish white, about 4 mm. long, 

 elliptical-oblong, acutish : hoods erect-spreading, broadly truncate 

 at the summit, truncate at the hastate-sagittate obscurely clawed 

 base ; ventral margins with rounded angles or lobes at the middle, 

 somewhat involute : horn flat, arising from the keel of the hood 

 near its base, arcuate, horizontally long-exserted over the anthers, 

 often dorsally angled at about the middle : anther-wings very slen- 

 der, minutely notched at the angled base. Follicles not seen. 



Southwestern Texas: Lindheimer, nos. 348 and 631 in Herb. 



Gray, no. 456 in Herb. U. S. Nat. Mus. ; Guadalupe, 105 miles 



southwest of San Antonio, Edward Palmer, no. 810 iji Herb. Gra\ 



