vary much branched, often with remarkably small leaves, and not rarely with edible fruits. Among them many rhamnaceous and celastraceous shrubs, and some Euphorbiaceae, were particularly conspicuous, as well as some Mimoseae, one of which I must not forget to mention, because it is perhaps the smallest shrub in this family; not more than one or two inches high, with diminutive leaflets, but large purple flowers; it was collected near Chihuahua.
One of the most offensive of these chaparrál shrubs was the Koeberlinia, Zucc, called here Junco, (Gregg.;) a small tree rather than a shrub, about 10 feet high, stem 4 to 6 inches in diameter; wood hard, dark brown with white alburnum; terminal branches green, with a dark brown spinous termination, 1 to 2 inches long, and 112 to 2 lines in diameter; very small subulate leaves soon deciduous; small white flowers in short lateral racemes; fruit not seen; in flower in May. It was frequently seen from south of Chihuahua to Monterey, (and Matamoros, Gregg.)
We find here again the interesting Chilopsis mentioned above, (see note 11,) also Larrea glutinosa, (note 10,) and another zygophyllaceous shrub, a true Guajacum,[1] which appears to be an undescribed species; it belongs to those plants that connect the Mexican with the Texan flora, as we find it extending from Parras to Monterey, and from there to the Upper Colorado, in Texas, Tecoma stans reappeared here with smaller pubescent leaves and more alate petiole, though probably not distinct from the larger and smoother plant found below Paso.
The beautiful Fauquiera splendens, (see note 16,) with its panicles of long tubular crimson flowers, rose here above all other shrubs; in some instances it reached a height of from 20 to 30 feet, and perhaps more, always in single stems.
A few species of Yucca, together with Opuntia arborescens, (note 5,) formed almost the only trees on the arid plains. But in the valley of the Nazas occur stately trees of a species of Algarobia. distinct from the A. glandulosa of the north, with broader legumes, larger seeds, and few or no glands on the leaves.
About Saltillo Echinocactus texensis, Hpfr., (E. Lindheimeri, Engelm., in Plant. Lindh. 1. c.,) was found, which extends from here to Matamoros, and to the Guadaloupe and Colorado, in Texas. The pretty Mammmillaria strobiliformis,[2] so grows on rocks near Rinconada. Hunne-
- ↑ Guajacum angustifolium, n. sp. foliis sub-5 (4-8) jugis glaberrimis, foliolis oblongo linearibus, reticulatis; pedicellis et basi calycis pubescentibus; ovario bilobo, pubescente; capsula bivalvi, seminibus 2 ovatis.
About Parras; collected also by Dr. Gregg, who has found the plant common from Monclova to Parras, Monterey, and Camargo; found by Mr. Lindheimer on the Pierdenales river in Texas; flowers in April and May. Shrub or small tree with very knotty branches; leaflets mostly in 5 or 6 pairs, only on young vigorous shoots 6 to 8 pairs, mostly only 4 lines long, 12 to 1 line wide, reticulated on both sides. Purple flowers 6 lines in diameter; seeds yellow, of the size of small beans. The hard and heavy yellowish brown wood is called "Guajacan" about Saltillo, and used as a sudorific and in venereal diseases. (Dr. Gregg.)
- ↑ Mammillaria strobiliformis, n. sp., simplex ovato conica, tuberculis imbricato-adipresssis, conicis, applanatis, sulcatis; aculeis rectis radialibus
