﻿PLANTS FENDLERIAIVUE. 71 



(caeruleis vel albis) angusto-linearibus involucrum subduplo superantibus ; pappo persis- 

 tente e paleis crassis cartilagineis uniserialibus basi concretis coroniformi, fl. radii brevis- 

 simo subaequali, disci inaequali, paleis 1 - 3 in squamellis aristiformibus productis corollam 

 atque achenium late obovatum calloso-marginatum pi. m. brevioribus. — Sides of high 

 mountains, Santa Fe Creek, and prairies on the Mora River ; June to Aug. (353). — 

 The most striking species of the genus ; the upright stems 6 or 7 inches high from a 

 strong tap-root, terminated by solitary heads resembling those of T. grandiflora or still 

 larger (an inch in diameter). Lowest leaves 2 inches long ; the upper successively 

 smaller and more sessile. Ray achenia fertile, narrower than those of the disk, which 

 are a line and a half in length, flat, with thickened callous margins. The pappus is of 

 a much firmer texture than in the other species, more paleaceous, the scales few, coroni- 

 form-concreted, and perfectly persistent ; the 1 to 3 longer ones (of the disk) subulate- 

 aristiform, half or two thirds the length of the mature achenium. — Lieut. Abert also 

 gathered this species on Purgatory River. 

 * f341. Egletes humilis, Torr. &• Gray! FL 2. p. 411, in obs. (Leucopsidium hu- 

 mile, Benth. PL Hartweg, p. 18.) Valley of Santa Fe Creek ; May. (373.) — This is 

 also in Dr. Gregg's North-Mexican collection. The plant is more canescent and the 

 heads smaller than in E. Arkansana, and the pappus, as noted in the Fl. N. America, L c, 

 is a small crown, the edge of which is evenly cleft into a fringe of numerous setulose teeth. 

 The tube of the disk corolla sometimes becomes thickened and indurated at the base, as 

 in E. Arkansana.* 



* It is difficult to say whether this genus should be referred to the Anthemidese or the Asteroideae ; but if 

 Leucopsidium, DC, has been correctly joined to it, so likewise should be Aphanostephus, DC, which differs in 

 no character of any generic consequence. In E. ramosissima (Aphanostephus ramosissimus, DC, and also 

 A. Riddellii, Torr. 8f Gray) the coroniform pappus is minutely fringed, just as in E. humilis. I have had it in 

 cultivation for two years, along with E. Arkansana, with which it well accords in habit. The heads are 

 smaller, but more numerous, and are borne in profusion throughout the summer ; the rays are white, and usu- 

 ally finely tinged with pink or purple underneath. I have not observed any thickening of the disk-corollas. — 

 I no longer doubt that Keerlia skirrobasis of De Candolle is founded on a depauperate state of Egletes Arkan- 

 sana. Dr. Gregg collected specimens of E. ramosissima at Monterey and Buena Vista. — I subjoin the 

 characters of some new heterochromous Compositse-Asteroidese of Northern Mexico. 



PSILACTIS, Nov. Gen. 



Capitulum multiflorum, radiatum, heterochromum ; fl. radii ligulatis, numerosis, uniseriatis, faemineis ; disci 

 tubulosis hermaphroditis. Involucrum disco brevius, e squamis lanceolatis subherbaceis imbricatum, 3-4- 

 seriale. Receptaculum convexum, subalveolatum. Ligulse 60 - 80, elongatse, angusto-lineares. Corolla^ 

 disci 5-dentatse. Styli rami breves, appendice triangulari acutiuscula complanata hirtella lerminati. Achenia 



