ROBr.VS«^;.V. — DIAGXOSES KTC. OF SPEKMATOPHYTES. 5^/7 



D. aurantia iL.^, cornb, nov. yl^if^r aurantiuis L. Sp. PJ. ii. 877 

 (\~')y>). Anicr ameri/MniM, foliu jAnnatU, etc., Rel. Houst. 7, t. IS 

 (17HI). Dyfsodia append irru/ata Laj?. Xo%'. Gen. et Spec. 29 (IHUi). 

 Clomenoeoma aurantia (L.) Cass. Diet. Sci. Xat. ix. 416 0817;, lix- 

 66 fl829j. Clapina aurantiaca Benth. in Hrx^k. Ic. xii. t. 1104 (1872). 



D. aurantiaca '^Brandegeej, comb. nov. Jlyracnaf.herura aurantw.- 

 frara liranrJegee, Zo^,-, v. 2.% ri9fJ8;. 



D. pentachaeta (\)(..), cornb. nov, Ilyrritrri/dherura Berlandieri 

 DC. Prod. \. fU2 fl8^J6j. //. yenimhadum DC. I. c; Gray, Proc. 

 Am. Acad. xix. 42 (1883), where the two species of DeCandoUe are 

 united under the name of the latter from the standpoint of jiriority of 

 position. Thyraophylla perdfu:hoMa (l)(l.) Small, Fl. S. fi!. C .S. 

 1295, \?A\ (YM)'i). In making the tran-sier to Dyfssiodia the author 

 would ha\'e preferred to reinstate the first name employe^] by Dtdan- 

 dolle, but this is forbidden by Art. 46 of the International Rules, 

 which reads, " When two or more groups of the same nature are unite^J, 

 the name of the oldest is retained. If the names are of the same fJate, 

 the author chooses, and hLs choice cannot be mollified by .subsequent 

 authors." In the case in hand, the two names Berlandieri and 

 Xjerdar:hadurn were of the same date. The species seem first to have 

 been uniterj by Gra\', who chose the second of the two names, and this, 

 of course, is decisive according to the article just quoted- 



D. concinna (Gray), comb. nov. Hyraenatherum concinnura 

 Gray, <yn. Fl. i. pt. 2, 446 (1884). 



D, diffusa ''Gray;, comb. nov. Hymen^jtherum diffusum Gray, 

 PI. Wright, i. 116 fl8o2). 



D. Greggii (Grayj, comb. nov. Thymophylla Greggii Gray, PI. 

 Fendl. 92 (1849). Tkymophyllum Greggii (Gray) HenLsl. Biol. Cent.- 

 Am. Bot. ii. 221 (1881). Hymenatherum Greggii Gray, Proc. Am. 

 Acad. xix. 42 0883). 



D. Hartwegi (Gray), comb. nov. Hymenatherum Berlandieri 

 Benth. PI. Hartw. 18 (1839), by error of determination, not DC. 

 H. HaHwegi Gray, PI. Wright. L 117 (1852). 



D. Neaei ^DC), comb. nov. Hymenatherum, ? Xeaei DC. Prod. v. 

 642 1S36.. H. fxjeheroides Gray, PI. Wright, i. 115 (1852;. H. 

 Xaei Hemsl. Biol. Cent.-Am. Bot. ii. 220 (1881); Gray, Proc. Am. 

 Acad. 'xix. 41 'IHsZ . 



D. neo-mexicana Gray), comb. nov. Adenophyllum Wrightii 

 Gray, PI. Wright, ii. 92 (1853). Hymenatherum neo-mexicanum Gray, 

 Proc. Am. Acad. xLx. 40 (1883), not H. Wrightii Gray, PI. Fendl. 89 

 (1849). 



