252 Engelmann and Gray, 



upper surface of which is excavated. The membranaceous 

 cusps of the anther are triangular acute, and partly cover the 

 very obtusely 5-angular and somewhat convex stigma. The 

 small horizontal pollen-masses are oblong, slightly curved, and 

 scarcely attenuated at the exterior (attached) end. — From 

 the description, there can be little doubt that this plant is a 

 congener of Chthamalia biflora, and C. pubiflora, Decaisne, 

 in DC. jirodr., from which it differs in the glabrous corolla, 

 etc. ; but surely it cannot be separated from Gonolobus, as that 

 genus is left by Decaisne. The corona of Gonolobus, charac- 

 terized as " annuliformis undulato-lobata, lobis integris prom- 

 inentibus," exhibits great diversities in the admitted species, 

 from the proper annular and 5-lobed crown of G. lsevis, to 

 the campanulate one, with 10 long subulate and 5 short trian- 

 gular teeth, of G. macrophyllus and G. hirsutus. 



274. Eustoma Russellianum, Don, Griseb. Clayey, wet 

 prairies. July — August. 



275. Phlox Drummondii, Hook. Sandy soil, near water 

 courses. 



276. Convolvulus (Stylisma) Pickeringii, Torr. Dry, 

 sandy prairies. May — July. — Specifically distinct, we sus- 

 pect, from the C. tenellus, Lam. to which Choisy joins it. 1 



277. Cuscuta cuspidata (3. Vide No. 125, supra. Bot- 

 tom lands of the Colorado River. August. 



278. Lithospermum brevielorum (n. sp.) : caulibus soli- 

 tariis, vel plurimis e radice nigro-purpurea fusiformi erectis 

 apice ramosis, foliisque linearibus lineari-lanceolatisve margine 

 revolutis utrinque strigoso-canescentibus ; floribus subpedicel- 

 latis ; corolla calycis lacinias lineares strigosas vix sequante 

 fauce exannulata, lobis erectis (an semper?) minutissime 

 crenulatis ; nucibus albidis nitidis ovatis acutis, intus acute 



1 The collection also comprises a few specimens of Convolvulus hastatus, Nutt. 

 in Trans. Am. Phil. Soc. (n. ser.), V. p. 174 : which name, being sevpral times pre- 

 occupied, we propose for it the name of C. lobatus. Sandstone rocks, near Industry. 

 May, June. Stems prostrate, 8-4 feet long. Flowers rather small, white. Dr. 

 Wright has also sent it from the Colorado. 



