PLANT.E WRIGHTIANiE. 11 



Mexican collection from Zimapan, and other New Mexican specimens from Dr. 

 Gregg. But Dr. Engelmann has remarked the same thing in some of Lindheimer's 

 Texan specimens of P. trachysperma, which, as already remarked, can hardly be 

 more than a Northern, smaller-flowered form of P. uniglandulosa. 



20. WisLizENiA REFRACTA, Engelm. in Wisliz. Mem. N. Mex., p. 15. (Tab. II.) 

 Along the Eio Grande, five miles below El Paso ; Sept., in floAver and with abun- 

 dant ripe fruit. — This very remarkable and quite handsome Capparidaceous plant, 

 abundantly gathered by Mr. Wright in the region where it was discovered by the 

 enterprising scientific traveller whose name it bears, is so well characterized by 

 Dr. Engelmann, as to leave nothing of any importance to add, except to give a 

 figure, with analyses, made by Mr. Sprague from his own dissections. From 

 Oxystylis, Ton: Sf Frem., which I have barely seen in Dr. Torrey's herbarium, it 

 seems to be well distinguished by the characters adduced by Dr. Engelmann, by the 

 filiform (not gladiate and spinous) style, and by a marked difference in habit. — 

 The subjoined note on the species of the allied genus Cleoniella, drawn up some 

 time since, has been recently communicated by Professor Torrey.* 



* Notes on CLEOMELLA ; by John Torrey. 



This genus was founded by De Candolle, on an unpublished drawing of a Mexican plant, of which 

 specimens seem to be almost unknown in European herbaria. The description of De Candolle is brief 

 and unsatisfactory. It was with doubt that I referred to his Cleomella Mexicana a plant found in Western 

 Arkansas by Dr. James, in Long's first expedition. The latter plant was afterwards detected by Mr. 

 Drummond, in Texas, and by Mr. Beyrich, on the Upper Platte. It was described and figured by Sir 

 William Hooker, in the first volume of his Icones, as C. Mexicana, and described under the same name 

 in the Flora of North America, as well as in the recent Genera Illustrata of Dr. Gray. Another 

 species of the genus was discovered by Colonel Fremont, in California, and published in his second re- 

 port. About three years ago I received from Dr. Halsted excellent specimens of a Cleomella, which he 

 collected on the march of our army from Vera Cruz to the city of Mexico. This is probably the orig- 

 inal species of De Candolle, as it seems to be exclusively Mexican, while the Cleomella of Texas and 

 Arkansas has not been found beyond those States, except in their immediate borders. I have, therefore, 

 changed the name of the latter plant. A fourth species of the genus was discovered by Dr. Gregg in 

 Chihuahua and San Luis Potosi, in 1847 and 1848. The following synopsis will exhibit the leading char- 

 acters of all the species. 



1. Cleomella Mexicana (DC.) : foliolis spathulato-obovatis obtusis vel retusis glabris ; bracteis ple- 

 rumque trifoliolatis ; ovario stylum brevissimum multoties superante stipitem subaequante ; capsula retusa 

 subbicorni stipitem superante; seminibus leevibus. — C. Mexicana, DC. Prodr. 1. p. 237; D. Don. in 

 Edinh. New Phil. Jour., Jan. 1831. — Hab. Mexico, Mo^ino 4" Sesse, ex De Candolle. Between Vera 

 Cruz and the city of Mexico, Dr. Halsted. — This species is about a foot high, much branched, and ap- 

 parently diflTuse. The leaflets are about one third of an inch long, quite glabrous, somewhat fleshy, and 

 mucronate with a short bristle. The petiole is about as long as the leaflets. Stipules minute, subulate and 

 entire. The golden-yellow flowers are in terminal racemes, which are finally much elongated. Petals 

 about three times the length of the sepals. Pod 6 - 8-seeded, almost two-horned by the projecting upper 

 angles of the valves, the breadth (about 3^ lines) nearly twice as great as the length. Fructiferous pedi- 

 cels 4-5 lines long. 



2. C. LONGiPES (sp. nov.) : foliolis spathulato-obovatis obtusis vel retusis integerrimis vel margine ser- 

 rulato-scabris ; bracteis superioribus slmplicibus ; ovario stylum bis superante stipite pluries breviore ; cap- 

 sula retusa subbicorni stipite subduplo breviore. — Hab. Valley near San Pablo, Chihuahua, and near 

 San Francisco, San Luis Potosi, Mexico, Dr. Gregg. Collected in flower only, April 29th, and in both 

 flower and fruit, Dec. 28th. — Difl^ers from the preceding in the considerably larger and less conspicuously 



