350 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Pentarrhaphis, established by Kunth,° was based upon P. scabra, 

 which remained practically unknown until Hackel and Scribner iden- 

 tified it and added another species in 1890. 6 Since the addition of 

 this second species it is best separated from the other genera by its 

 spikes of 2 spikelets, one of which is aborted in P. scabra. There 

 appears to be no other character upon which it can be segregated. 



The monotypic genus Triaena c is separated by its spikes of a 

 single spikelet. With it will naturally fall Bouteloua unijlora when 

 this character alone is considered, but the latter species is manifestly 

 very closely related to B. curtipenduh. Indeed, it is quite probable 

 that further collections may prove that the former is simply an 

 unusual form of the latter. 



BIBLIOGRAPHICAL NOTES. 



There has always been a question regarding some of Lagasca's 

 names. Kunth's figures/ however, are recognizable by one who is 

 familiar with the species. The examination of a large number of 

 authentic specimens has elucidated many obscure names, but there 

 are a few more that, unless more evidence can be found, will always 

 remain doubtful species. 



Cervantes's e names published under the genus Erucaria have been 

 rejected almost in toto. It would be very desirable to refer these 

 names properly, although it is not probable that they would seriously 

 affect the synonymy. 



The next most difficult work to interpret is that of Fournier/ 

 Fragments of specimens cited from European herbaria have assisted 

 greatly in settling doubtful questions. The examination of a cited 

 number, however, is not sufficient to identify Fournier's species, for 

 different species are found at times under the same number in different 



a In H. B. K. Nov. Gen. & Sp. 1: 178. pi. 60. 1816. 



& Bull. Torrey Club 17: 233. pi. 108. 1890. 



cH. B. K. Nov. Gen. & Sp. 1 : 178. 1816. 



d H. B. K. Nov. Gen. & Sp. 1 : pi. 51-60. 1816. 



e La Naturaleza 1 : 347. 1870. 



/ Mex. PI. 2 : 1881. There is a difference of opinion about the proper date to cite 

 for this work. It seems desirable to bring together here the available facts which 

 appear to be as follows: 



1. Fournier read a paper before the Academy of Sciences of Paris, June 10, 1878, in 

 which he stated that this work was completed and in which he gave data regarding 

 the distribution and number of species. (Compt. Rend. Acad. Sci. (Paris) 86 : 1441. 

 1878.) 



2. Bentham received in 1881 a copy marked "proof sheets" (see Hitchcock and 

 Chase, Contr. Nat. Herb. 15:49. 1910) with neither index nor title page. (Journ. 

 Linn. Soc. Bot. 19 : 14-134. 1881.) 



3. Hackel also received a copy of the work excluding title page and terminating 

 with page 144 (18 sheets) in 1881. 



