174 Floristik, Geographie, Systematik etc. 



Concise descriptions of certain desert regions of south-central 

 Mexico are given, and the characteristic xerophytic Vegetation of 

 these areas is well illustrated by Photographie reproductions in half- 

 tone. The greater part of the paper is taken up by the descriptions 

 of new species, some of which are carefully illustrated b}^ line 

 drawings. Several new combinations are formed, and in each instance 

 the proper synonym is associated. The genera for the most part are 

 unaccompanied b}?' keys to the species. All tj^pes of new species are 

 deposited in the United States National Herbarium. 



The following new species and new combinations are included 

 under the authorship of Dr. Rose unless otherwise indicated : Beau- 

 carnea guatemalensis n. sp., B. tner}nis {Dasylirion inerniis Wats.), 

 B. oedipus n. sp. , B. pliabilis {Dasylirion plinbile Baker), B. ptirpiisi 

 n. sp., Dasylirion lucidum n. sp. , Calibanus n. gen. [Liliaceae), C. 

 caespitosiis {Dasylirion caepitosum Scheidw.), Nolina elegans n. sp., 

 N. nelsoni n. sp., N. pumila n. sp. , Echeandia paniculata n. sp., E. 

 reflexa {Anthericum reflexuni Cav.), Castalia gracilis {Nymphaea gra- 

 cilis Zucc), C. pringlei n. sp., Clematis rhodocarpa n. sp., C. rufa 

 n. sp., Potentilla losani Rose & Painter n. sp. , Alcheniilla procumbens 

 n. sp., A. stibalpestris n. sp., Pithecolobium revolutum n. sp., Bau- 

 hinia confusa n. sp., B. goldinani n. sp., B. longiflora n. sp., Cassia 

 arida n. sp., C demissa n. sp. , C. durangensis n. sp., C. goldttiani 

 n. sp,, Hojfnianseggia arida n. sp., H. watsoni {Caesalpinia watsoni 

 Fisher), Benthainantha edwardsii {Cracca edwardsii Gray), B. bicolor 

 {Cracca bicolor Micheli), B. fruticosa n. sp., B. glandulosa n. sp. , 

 B. pwnila n. sp., Cologania losani n. sp., C. tenuis n. sp., Dolicholiis 

 cuernavacanus {Rhyucliosia cuevnavacana Rose), D. discolor {Rhyn- 

 chosia discolor Mart. & Gal.), D. hondurensis n. sp., D.longeracemosns 

 {Rhynchosia longeracemosa Mart. & Gal.), D. macrocarpiis {RJiyn- 

 chosia macrocarpa Benth.), D. nelsoni n.s'p., D.nigropnnctatns {Rhyn- 

 chosia nigropiinctata Wats.), D. precatorins {Glycine precatoria (Humb. & 

 Bonp.), D. pringlei {Rhyiichosia pringlei Rose), D. vailiae n. sp., Odo)iia 

 acapnlcensis {Galactia acapidceiisis Rose), O. brachystachys {Galactia 

 brachystachys Benth.), O. multißora {Galactia mitltißora Robinson), 

 O. wrightii {Galactia wrightii Gray), O. inca)ia n. sp., O. retnsa n. sp. , 

 O. viridiflora n. sp., Parosela insignis {Dalea i)isignis Hemsl.), P. gla- 

 berrima {Dalea glaberrima Wats.), P. polyphylla {Dalea polyphylla 

 Mart. & Gal.), P. citriodora {Dalea citriodora Willd.), P. niucronata 

 {Dalea miicronata DC), P. pectinata {Dalea pectinata Kunth), P. niu- 

 tabilis {Psoralea nmtabilis Cav.), P. trochilina {Dalea trochilina Brandg.), 

 P. hernsleyana n. sp. , P. leiicostachys {Dalea leucostachys Gray), P. 

 eysenhardtioides {Dalea eysenhardtioides Hemsl.), P. oaxacana n. sp.), 

 P. navicidifolia {Dalea navicidifolia Hemsl.), P. tuberculata {Dalea 

 tnberculata Lag.), P. psoralioides {Dalea psoralioides Moric), P. ca- 

 nescens {Dalea canescens Mart. & Gal.), P. iuconspicua {Dalea incoji- 

 spicua Schauer), P. vetida {Dalea vetnla Brandg.), P. cliffordiana 

 {Dalea clißordiana Willd.), P. revoluta {Dalea revoluta Wats.), P. lae- 

 vigata {Dalea laevigata G. Don), P. cyanea {Dalea cyanea Greene), P. 

 nigra {Dalea nigra Mart. & Gal.), P. erythrorhisa {Dalea erythrorhisa 

 Greenm.), P. Inisiana {Dalia liiisiana Wats.), P. sericea {Dalea sericea 

 Lag.), P. gracilis {Dalea gracilis Kunth), P.painterin.'&\).^ P.paiicißora 

 n. sp., P. watsoni n. sp., P. eriophylla {Dalea eriophylla Wats.), P. 

 seemani {Dalea seemani Wats.) , P. argyrostacJiys {Dalea argyrostachys 

 Hook. & Arn.), P. phnnosa {Dalea phtmosa Wats.), P. leiicostonia 

 {Dalea leiicostoma Schlecht.), P. piirpiisi {Dalea pnrpnsi Brandg.), 

 P. berlaiidievi {Dalea berlajidieri Gray), P. micropJiylla {Dalea micro- 



