V 



PLANT^ WRIGHTIAN.F. 



33 



Hiimboldtiana, IL B. K Nov. Gen. 8r Sj). 7. p. 40. t. 618. R. biniflorus, DC. Prodr 

 2. p. 26? R umbellatus, Cau.T — Eocky hills, Turkey Crcck, Junc ; in flower 

 Also near Monterey, Berlandier, Gregg. Nortli of Quercfaro, Gm;y (in fruit), 

 Sonora Alta, Real dcl Monte, and Zimapan, Coulter (No. 1 - 3), and Califonila, Na 



113, Coulter. New Mexico, Wisli 





that 



this is a shrub, from 2 to 3, or sometimes, according to Grcgg, from 4 to 12 fcct in 

 height. Thcre is probably an error, thorefore, in Kunth's statcmcnt that Ilura- 

 boldfs specimens were from an " arbor proccrrima." For our plant scems to be the 

 Rhamnus Humboldtiana, as wcll from Schlechtendars account of original spcci- 

 mens, as from Kunth's charactcr and ficrure, exce])t that the latter, but not the de- 



rep 



The species varics much 



of the leaves, &c., and in the number of flowcrs in the axillary clustcrs, just as do 

 most Rhamni. Wrighfs and most of our specimcns have them raised on a short 

 common peduncle, as in K. Humboldtiana. I cannot think that K. glandulosa is 

 distinct, nor is the name a good one. The leaves are only pcllucid-punctatc. Thc 

 2-3-ceIIcd ovary has two ovules in each cell. The mature drupe is ovoid, 4 or 5 

 lines long, ripening from one to three sccds. Rhamnus biniflorus, Hook. 4« Arn., 

 is anothcr species of this genus. 



90. CoLUBRiNA Texensis, Gray, Fl. Lindh. 2. w. 169. Rhamnus? Tcxensis, 



^^ 



8f Gray, Fl. 1. «. 263. On the Leona, June; in fruit. Common throu 



e> 



riiis is a low, divaricately much-branched and sprcading, flexu- 

 ose shrub, from 2 to 4 feet high, flowcring from March to May. In Lindheimer's 

 collection of 1850 are fine specimens of what I take for a larger-leaved variety of 

 C. Texensis, but -svhich Dr. Engelmann, under the name of Coluhrina stricta, con- 



siders as specifically distinct. It is " 



lcafv 



end of the slender branchlets, from 5 to 10 feet high; the leaves pendulous (much 

 as in a Cerasus), larger, and it flowers much later (June 15), than C. Texensis; the 

 flowers and fruit are much the same." Engelm. The leavcs on vigorous sterile 

 branches are often fully 2 inches long, oval or ovate-oblong, with a roundcd base, 

 softly silky-tomentose underneath. These larger leaves on sterile branches are com- 

 mon to our Zizyphus, to Condalia obovata, and other Rhamnaccse, as Dr. Engel- 

 mann remarks. 



MICRORHAMNUS, Nov. Gen. 



Calyx coloratus, 5-fidus ; tubo expanso subplano ; lobis patcntissimis, ovatis, tri- 

 nervatis, ncrvo medio intus carinatis. Discus carnosus, pateriformis, calycis tubo 

 adnatus, margine subundulatus, ovarium superum cingens. Petala 5, obcordata, 

 unguiculata, calyce breviora. Stamina 5, petalis aequalia, iisdem libera : antherae 

 didymae, biloculares, bivalves. Ovarium libcrura, ovoideum, biloculare, in stylum 

 columnarem angustatum: stigma emarginatum, Ovula solitaria. Fructus subdru- 

 paceus, siccus, ovoideus, osseus, calycis cupula parva suff^ultus, abortu snbunilocula- 

 ris monospermus. Cotyledones foliaceae, oblongae, planae. — Fruticulus ericoideus, 



ramosissimus, slaber: ramis 



foliis altemis et in axillis vel 



brevissimos fasciculatis, pcrsistentibus, parvis, linearibus vel spa 



