STANDLEY TEEES AND SHRUBS OF MEXICO. 535 



16. Zanthoxylum moUissimum (Engl.) P. Wilson, Bull. Torrey Club 37: 86. 

 1910. 



Fagara mollissima Engl. Bot. Jahrb. Engler 21: Beibl. 54: 22. 1S96. 



Known only from the type locality, Mina de Dolores. 



Leaflets 9 to 11, 4 to 8.5 cm. long, entire or nearly so, densely pubescent. 



17. Zanthoxylum goldmani Rose; P. Wilson, N. Amer. Fl. 25: 195. 1911. 

 Known only from the type locality, between Culiacan and Las Flecbas, 



Sinaloa. 

 Branches prickly ; leaflets 7, coriaceous, crenate, pubescent beneath. 



18. Zanthoxylum arborescens Rose, Contr. U. S. Nat. Herb. 5: 112. 1897. 

 Zanthoxylum peninsulare T. S. Brandeg. Zoe 5: 249. 1908. 



Southern Baja California and Sinaloa ; type from Imala, Sinaloa. 

 Small tree, 3 to 4 meters high, the branches unarmed or with few short 

 prickles ; leaflets 3 to 7, pubescent. 



19. Zanthoxylum microcarpum Griseb. Fl. Brit. W. Ind. 138. 1859. 

 Fagara rnicrocarpa Krug & Urb. ; Urban, Bot. Jahrb. Engler 21: 570. 1896. 

 Oaxaca. Costa Rica ; Lesser Antilles ; South America ; type from Dominica. 

 Tree, sometimes 13 meters high, the bark covered with stout compressed 



prickles; leaflets 10 to 30, oblong or oblong-lanceolate, 3 to 9 cm, long, acute, 

 serrate-crenate, pubescent or glabrate ; panicles terminal, 10 to 15 cm. long ; 

 follicles 1 or 2, 4 to 5 mm. in diameter. 



DOUBTFUL SPECIES. 



Fagara falcifolia Engl. Bot. Jahrb. Engler 21: Beibl. 54: 24. 1896, Type 

 from Mirador, Veracruz. Based upon sterile specimens. 



Zanthoxylum pentanome DC. Prodr. 1 : 725. 1824. Described from Mexico. 

 Referred doubtfully by Wilson to synonymy under Z. monophyllum (Lam.) P. 

 Wilson. That, however, is not represented by herbarium specimens from 

 Mexico. It is distinguished by 1-foliolate leaves. The name Z. pentanome 

 has been much used in works relating to Mexican plants. Some species so 

 named is reported to be a remedy for the " v6mito negro " and for venereal dis- 

 eases. It is said to be known as " palo mulato." 



12. PILOCARPUS Vahl, Eclog. Amer. 1: 29. 1796. 

 The leaves of P. jaborandi Holmes and P. microphyllus Stapf, of Brazil, are 

 oflicial in the U. S. Pharmacopoeia, and leaves of other species also are used. 

 They contain two alkaloids, pilocarpine and jaborine, which are the most reli- 

 able of diaphoretics. They are widely employed for the treatment of dropsy, 

 pleurisy, rheumatism, Bright's disease, and similar affections. 



1. Pilocarpus longipes Rose, Contr. U. S. Nat. Herb. 5: 112. 1897. 



Pilocarpus insularis Rose, U. S. Dept. Agr. N. Amer. Fauna 14: 80, 1899. 



Tepic to Guerrero ; type from Acapulco, Guerrero, 



Unarmed shrub or tree, 2 to 6 meters high ; leaves alternate, pinnate, the 

 leaflets usually 3 or 5, oblong to obovate, 3 to 10 cm. long, obtuse or refuse, 

 entire, glabrous ; flowers small, racemose ; fruit of 1 or 3 carpels, these con- 

 spicuously ridged ; seeds large, black. 



Perhaps not essentially different from P. racemosus Vahl, of the West Indies. 



13. ESENBECKIA H. B. K. Nov. Gen. & Sp. 7: 246. 1825. 



Unarmed trees or shrubs ; leaves alternate or rarely opposite, simple or 1 to 

 5-foliolate, the leaflets gland-dotted ; flowers small, perfect, racemose or panicu- 

 late; fruit a hard woody capsule, very rough outside. 



