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Art. IV. — Plantce Heermanniance. Descriptions of New Plants, collected in South 

 California by Dr. A. L. Heermann, Naturalist attached to the Survey of the 

 Pacific Railroad route, under Lieut. R. S. Williamson, U.S.A. With remarks on 

 other Plants heretofore described and belonging to the same collection.* 



By E. Durand and Theod. C. Hilgard, M. D. 



PAPAVERACE^. 



ARGEMONE munita, nova species. Caulis erectus ramosus, 2?-pedalis. Tota 

 planta glaucissima tenera et, maxime in ramis foliorumque marginibus, aculeis albis 

 retrorsis horrens. Folia subamplexicaulia, elongato-cordata, valde repando-sinuata 

 undulata. Flores in apicibus 3-4 conferti, breviter divaricateque pedunculati. 

 Calyx 3-sepalus caducus setosus, quoque sepalo cornuto, cornu in aculeum validum 

 desinente. Corolla 6-petala maxima, 3-4" diametro ; petalis cuneato-obovatis, mar- 

 gine denticulatis, albis recte venosis. Germen lanceolato-cylindricum, aculeis rectis 

 dense obtectum. Capsula adhuc ignota. 



Stem branching, about 2| feet high. The whole plant very glaucous and, chiefly 

 on the stems and margins of the leaves, densely covered with strong and slightly 

 retrorse prickles. Leaves subclasping, elongate-cordate, deeply repando-sinuate and 

 undulate. Flowers in clusters of 3-4 on short divaricate peduncles. Calyx 3-sepa- 

 lous, prickly, each sepal bearing a horn terminating in a strong prickle. Corolla 3-4" 

 in diameter ; petals six, white, veined, with slightly denticulate margins. Germ lan- 

 ceolate, cylindrical, densely covered with erect prickles. Capsule unknown. 



The specimens submitted to our examination are incomplete and not sufficiently 

 advanced to determine the shape of the mature capsule and seeds. We have com- 

 pared it with various forms of A. mexicana and with the figure of Lindley's A. gran- 

 difktra in Bot. Reg. T. 1264. If the latter and our plant are but varieties of A. mexi- 

 cana, as Prof. Asa Gray thinks, they are two extreme forms of this very variable 

 species, the one being almost unarmed and the other densely prickly. Both Lindley's 

 and our plant bear large and beautiful white flowers; but in ours the texture 

 is more delicate than in the mexicana, and the habitus of the leaves and branches is 

 less acute, more rounded and undulating; the peduncles are shorter, stouter and 

 more divaricate. It grows in large patches at Williamson's Pass and was in full bloom 

 in August and September. 



* Try be republished, with figures, in Lieut. R. S. Williamson's Report. 



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