STANDLEY TREES AND SHRUBS OF MEXICO. 329 



Sesse and Mocino report ^ from Mexico Rubus occidentalis and R. hispidus, 

 both United States species, R. fruticosus, a European species, and R. pentha- 

 phifllus. The descriptions given are too brief for identification. 



The tropical American species of Rubus seem to have attracted little atten- 

 tion from the early writers, but they are mentioned by Oviedo (Lib. VIII, 

 Cap. XXVI), who says of the " zarzamoras : " "Although these can not be 

 counted as trees in Spain, they are so here, where they have thicker trunks 

 and stems and are much taller than in Castile, and for their size must be 

 termed trees." 



Leaves simple. Plants unarmed. 

 Flowers paniculate ; drupelets capped by a hard pubescent cushion. 



26. R. parviflorus. 

 Flowers mostly solitary ; drupelets without a cushion. 

 Leaves concolorous, the terminal lobe broadly ovate, usually broader than 



long 27. R. neomexicanus. 



Leaves dark green above, paler beneath, the terminal lobe triangular, usu- 

 ally longer than broad 28. R. trilobus. 



Leaves compound. 



Stipules broad, free or nearly so. Stems creeping 1. R. pumilus. 



Stipules narrow, linear-lanceolate or subulate, more or less adnate to the 

 petioles. 

 Fruit cup-shaped, falling off from the dry receptacle. 



Inflorescence racemose; fruit red; leaves pinnate 5. R. strig'osus. 



Inflorescence corymbose; fruit black or purple; leaves palmate. 



Fruit hemispheric; sepals inclosing the fruit 4. R. pringlei. 



Fruit oblong; sepals reflexed in fruit. 



Leaves glabrate on the upper surface ; fruit S to 15 mm. thick. 



2. R. glaucus. 

 Leaves puberulent on the upper surface; fruit 6 to 8 mm. thick. 



3. R. eriocarpus. 

 Fruit not cup-shaped, the carpels remaining on the fleshy receptacle and 

 falling with it or falling off separately. 

 Plants with prostrate biennial stems ; leaflets coarsely toothed, deciduous. 

 Leaves glabrous beneath or nearly so, except on the veins. 



25. R. humistratus. 

 , Leaves copiously pubescent beneath. 



Fruit sparsely pilose 23. R. cymosus. 



Fruit glabrous 24. R. oligospermus. 



Plants with usually erect or scandent perennial stems ; leaflets finely and 

 closely dentate, often evergreen. 

 Drupelets few, falling off separately. 



Plants scandent ; branches of the inflorescence unarmed ; sepals ob- 

 tuse. 

 Stems tomentose, unarmed ; leaflets stellate-puberulent on the 



upper surface, velvety-tomentose beneath 21. R. scandens. 



Stems inconspicuously pilose, prickly ; leaflets glabrous above, pu- 

 berulent beneath on the veins 22. R. fagifolius. 



Plants erect ; branches of the inflorescence prickly ; sepals acute or 



acuminate 11. R. corifolius. 



Drupelets united with the receptacle or, if falling separately, numerous. 

 Stems and petioles densely hispid with long eglandular bristles. 



6. R. trichomallus. 



' PI. Nov. Hisp. 85. 1887. 



