PLANTS NOViE THURBERIANjE. 301 



Sidalcea malvceflora, var. alhiflora, were abundant. At a camping-place near the Sierra 

 de los Animos a new Stephanomeria was collected. 



" The Sierra Madre, the back-bone of Mexico, was crossed by the Guadalupe 

 Pass, through which the persevering Colonel Cooke first took a wagon-train. The 

 descent in a few miles is about a thousand feet. The pass afforded Arctostaphylos 

 pungens, Rhus microphylla, Baccharis ramulosa,* Fouquiera splendens, Ceanothus 

 Greggii, and several Pentstemons. The small stream at the bottom of the pass is 

 thickly bordered by Platanus Mexicanus and Fraocinus velutinus. 



" The town of Fronteras was reached by striking off from Agua Prieta in a south- 

 erly direction. Upon the low hills between these two points were larger and more 

 abundant specimens of Fouquiera splendens than were seen in any other place. A 

 valley called Mabibi or Mababi, which lies between Fronteras and Bacuachi afforded 

 several new plants, among them an undescribed Ranunculus, an Astragalus, and a 

 Papilionaceous undershrub which has been doubtfully referred to Daiibentonia : also 

 Ruhus trivialis ! and the exquisitely beautiful Aquile^ia leptocera, var. flava. 



" From Bacuachi to Arispe the course of the Sonora Kiver was followed. Shortly 

 after leaving the former place, it passes through a narrow canon, the rocky walls of 

 which rise perpendicularly for several hundred feet on either side. The whole 

 pass Avas brilliant with the intensely scarlet flowers of a fine Erythrina, Avhich 

 projected from almost every crevice.-]- In this canon Avas first noticed a new 



* Baccharis ramulosa = Aplopappus ramulosus, DC, and Linosyris (Aplodiscus) ramulosa, Gray, 

 PI. Wright. 2. p. 80. Mr. Thurber appears to have gathered the male plant only ; and this alone occurs in 

 Wright's and other collections. But I have seen female specimens, collected by Dr. Bigelow or Dr. Parry, 

 which show, what was not before suspected, that this is a real Baccharis. In Thurber's specimens the bristles 

 of the pappus are clavellate-barbellate at the summit, which is scarcely noticeable in the original plant of 

 herk Martius : but Wright's No. 1400 is intermediate. — A. G. 



t This Erythrina is also in Gregg'a Mexican collection. No. 586 (without fruit) ; from Paso de Gallinero, 

 near Dolores, in Queretaro ? It accords so nearly with the imperfect character of E. coralloides, DC, that 

 I venture to apply that name to it ; although the petioles are often somewhat aculeolate, and the pods are 

 minutely cinereous-pubescent. According to Dr. Gregg's notes, it forms a shrub or small tree, from five 

 to ten feet high. Mr. Thurber remarks that the trunk is a foot in diameter, but subterranean. The short 

 and stout prickles are solitary under the leaves. The foliage, branchlets, dz-c. are minutely tomentose- 

 pubescent when young, at length glabrate. Leaflets dilated-ovate or deltoid-ovate, truncate at the base, 2 or 

 2| inches long and 2| to 3 inches wide, subcoriaceous. Raceme short and dense. Flowers 2 inches long. 

 Calyx 3 or 4 lines long, truncate, a little oblique. Corolla "brilliant scarlet"; the vexillum linear-oblong, 

 straight ; the wings and keel included in the calyx. Stamens 10. Pods 5 or 6 inches long, torose, cinereous- 

 puberulent, few-seeded, tipped with a cuspidate point of an inch in length, while the similar attenuated base 

 tapers into a stipe of the same length, tardily dehiscent. Seeds oval-oblong, a little over half an inch in 

 length, bright red, with a narrow and pale hilum. — A. G. 



