May 26, 1905.] 



SCIENCE. 



831 



changed a name and at the same time has 

 given a description of the species as he under- 

 stands it. The descrii)tion may not agree 

 with the historic type. If the author states 

 the synonymy in such a manner that there is 

 no doubt that he meant to change the name 

 of a given species, the old type must be re- 

 tained regardless of the description or the 

 specimens cited at the time the change is 

 made. This may sometimes become a ques- 

 tion of judgment to decide whether there is 

 primarily a change of name or a description 

 of a species with a doubtful reference to a 

 previously published species. For example: 



(a) Panicum harhipulvinatum Nash. Mem. 

 N. y. Bot. Gard. 1: 21. 1900. 



Panicum capillare hrevifolium Vasey; 

 Scribner, Bull. U. S. Dept. Agric. Div. Agrost. 

 5: 21; not Panicum hrevifolium L. 



Then follows an extended description and 

 finally a specimen is cited as the type (Ryd- 

 berg and Bessey 3544). This is evidently a 

 change of name and the type should remain 

 the same and be determined by a reference to 

 the original publication of P. capillare hrevi- 

 foUum Vasey, where a certain specimen from 

 Montana is mentioned, Kydberg & Shear 436. 

 Even though it may have been that the plant 

 described by Mr. Nash was a different species, 

 still the name P. harhipulvinatum Nash is a 

 typonym of P. capillare hrevifolium Vasey 

 and a new type can not be assigned. 



(h) Panicum scrihnerianum Nash. nom. n. 

 Bui. Torr. Bot. Club. 22: 421. 1895. 



Panicum scoparium S. Wats, in A. Gray, 

 Man. Ed. 6, 632. 1890. Not Lam. 



P. scoparium minor Scribn. Bui. Univ. 

 Tenn. 7 : 48. 1894. Not P. capillare minor 

 Muhl. 1817. 



The synonymy is arranged chronologically 

 and both names are vmtenable. I believe that 

 the fact that Mr. Nash chose scrihnerianum 

 for the new name is sufficient evidence to 

 show that he intended to change the name of 

 P. scoparium minor Scribn., and hence the 

 type of the former is also the type of the 

 latter, namely, a specimen from middle Ten- 

 nessee collected by Gattinger. 



Others may hold that the new name must 

 rest upon the type of the plant described by 



Watson, since this is the first synonym cited. 

 A reference to Watson's description shows that 

 P. paucifiorum is given as a synonym in the 

 6th edition of the ' Manual ' ; that the descrip- 

 tion is identical with that under P. pauci- 

 fiorum Ell. ? of previous editions back to the 

 first; that in the first edition the range is 

 given as N. Pennsylvania (Carey) and W. 

 New York to Michigan. In this case Carey's 

 specimen becomes the type of the species 

 doubtfully referred to P. paucifiorum Ell. by 

 Gray and also the type of P. scrihnerianum 

 Nash. 



(c) Panicum minus (Muhl.) Nash. Bui. 

 Torr. Bot. Club. 22 : 421. 1895. 



P. diffusum Pursh 1814. Not Swartz 1788. 



P. capillare minus Muhl. 1817. 



P. philadelpliicum Bernh. 1829. 



Mr. Nash then describes his plant briefly, 

 but sufficiently to show that it is not Muhl- 

 enberg's plant, but P. capillare minimum 

 Engelm. Nevertheless, the type of P. minus 

 (Muhl.) Nash must be that of P. capillare 

 minus Muhl. (which, by the way, was not thus 

 published by Muhlenberg), as there is pri- 

 marily a change of name. It might be argued 

 that P. diffusum Pursh is also a typonym of 

 P. minus Nash. If Mr. Nash had given an 

 entirely new name to P. diffusum Pursh, then 

 the new name would have been a typonym of 

 P. diffusum, but he chose to take up another 

 name founded upon a different type, in which 

 case P. minus Nash and P. diffusum are 

 synonyms or at least supposed to be, but they 

 are not typonyms. 



{d) Dactylis cynosuroides L. Spec. 71. 1753. 



Linnjeus gives first a description of his own 

 apparently based upon the specimen in his 

 herbarium, which is Spartina polystachya 

 Willd. ; second, a citation from Gronovius 

 Flora Virginica, which is supported by a 

 specimen of Spartina polystachya Willd. in 

 his herbarium; thirdly, a variety /? which is 

 Spartina glahra Muhl. The localities given 

 are Virginia, Canada, Lusltania. All the 

 evidence here is in one direction, and the tyjie 

 specimen is the one in the Linnssan herbarium. 

 Michaux next transfers this to his genus 

 Trachynotia as T. cynosuroides. As he uses 

 the specific name cynosuroides, and quotes as 



