PLANTS WRIGHTIAN.E. 9 



latere compressum, stylo sequilongum : stigma cordatum, bilobum, lobis ad pla- 

 centas respondentibus. Siliqua breviter linearis, septo angusto subenervi contrarie 

 plano-compressa, utrinque retusa, stylo conspicuo superata ; valvis naviculari-con- 

 duplicatis, dorso tenuissime uninerviis. Semina in loculis plurima (20-40), uni- 

 serialia, e funiculo libero pendula, ovalia, turgida, immarginata. Cotyledones 

 lineari-oblongse, planse, septo (ut videtur) parallelfe, radiculse adscendenti incum- 

 bentes. — SufFrutex humilis, piibe molli stellata canescens ; caulibus a basi ramosis 

 difFusis ; foliis spathulatis saepiiis repandis vel sinuato-dentatis in petiolum angus- 

 tatis; racemis laxis ; floribus majusculis albis ; siliquis cano-puberulis (6-8 lin. 

 longis) pedicello sequalibus vel sublongioribus. 



11. Greggia camporum. (Tab. I.) High prairies and calcareous hills, at the 

 head of the San Felipe; July (in flower and fruit). Also gathered, some years 

 since, " west of Parras " in Cohahuila, and later at Cerros Bravos, by Dr. Josiah 

 Gregg, the author of the " Commerce of the Prairies," and other writings on the 

 physical character, productions, and resources of New Mexico, and who has for 

 several years past been a most diligent explorer and collector of the botanical 

 treasures of New and Northern Mexico. Intelligence of his lamented decease, in 

 California, (from over-exertion in scientific investigation in the interior,) having 

 reached me while engaged in the study of this interesting plant, — one of his own 

 discoveries, — I dedicate the genus to his memory, and give to the species a name 

 that associates it with the plains of the Southwest, which this enterprising dis- 

 coverer has so largely explored and so ably illustrated. The genus formerly ded- 

 icated to Dr. Gregg by my friend and colleague. Dr. Engelmann, proves to be the 

 Cowania purpurea of Zuccarini, and is, without doubt, a true Cowania. — It will 

 be seen that the Cruciferous plant here described and illustrated, from Mr. Wright's 

 excellent specimens, is the same as that which is briefly noticed in Planta; Fend- 

 leriatia, p. 116, in a note, under Synthlipsis. It proves to have, as I suspected, 

 incumbent cotyledons, as well as other characters which abundantly distinguish it 

 from the last-named genus, notwithstanding the similarity in aspect and in the 

 lateral compression of the pods. If the pod be deemed a silicle, the genus would 

 fall into the tribe Lepidinete of De Candolle's arrangement, Avhere it would appear 

 to be out of place. If it be called a silique, the strong compression contrary to 

 the septum would seem to exclude it from the Sisymbrieae. The flowers are appar- 

 ently somewhat handsome ; the broad and rounded petals are nearly four lines 

 long, including the abrupt claw. — The mucilaginous mass Avhich envelopes the 

 seeds of most Cruciferfe when moistened is here pretty evidently seen to arise from 

 the disruption of delicate cells on the surface of the testa, and the uncoiling and 

 softening of a contained gelatinous coil, as in CoUomia, &c. 



12. Hymenolobus pubens (sp. nov.) : caule erecto ramoso racemisque prae- 

 longis densifloris pube stellata subcinereis ; foliis caulinis glabratis lanceolatis 

 oblongisve parce dentatis (imis ignotis) ; silicula ovali cinereo-pubescente stylo 

 brevi apiculata. — Margins of a pond, in a valley about eighty miles beyond the 

 Pecos ; August. — Annual or biennial, from twelve to twenty inches high, including 

 the fully-developed fruiting racemes, which are from six to ten inches long, rather 



