Rvdberg : Rocky Mountain flora 093 



and the form of the calyx, but the corolla is much smaller, only 

 15-20 mm. long, more strongly curved, and less funnelform. The 

 corolla of T. purpurea is 2-3 cm. long, and more open at the 

 throat. T. minuta has been reported parasitic on Lithophragma, 

 but may grow on other hosts. It has been collected in Oregon, 

 Washington, Montana, and British Columbia. 



Thalesia lutea (Parry) Rydb. comb. nov. 



Phelipaea lutea Parry, Am. Nat. 8 : 214. 1874. 



Aphyllon fasciculatum luteum A. Gray, Syn. Fl. 2 1 : 312. 

 1878. 



This differs from Thalesia fasciculata not only in the sulphur- 

 yellow corolla, but also in the acutish corolla-lobes and in the 

 acute rather than acuminate calyx-lobes. It is parasitic on grasses 

 instead of on composites, etc. 



Myzorrhiza Philippi, Linnaea 29: 36. 1857 

 Aphyllon § Nothaphyllon A. Gray, Bot. Calif. 1 : 584. 1876. 

 Orobanche § Myzorrhiza G. Beck, Bibl. Bot. 4: 78. 1890. 

 Following Beck von Mannagetta, many botanists in this 

 country have reduced Gray's section Nothaphyllon of Aphyllon 

 to Orobanche, while they have kept Thalesia distinct. Both, as 

 well as a part of Boschniakia, were included in Orobanche by 

 Beck. The editors of Gray's New Manual evidently took the 

 genus Orobanche in the same sense as Beck. In contrasting 

 Conopholis and Orobanche in the generic key, they give as charac- 

 ters for the former: "Calyx deeply cleft in front"; and for the 

 latter : " Calyx 5-cleft." On the following page, however, they 

 give as characters of Orobanche minor: "Calyx cleft before 

 and behind almost or quite to the base," and for O. ramosa : 

 "Calyx 4-lobed." 0. minor is the only typical Orobanche found 

 in this country, and this does not agree with the characterization 

 of the genus, as given in the New Manual. Evidently the editors 

 had Gray's genus Aphyllon in mind when the key was made.* 



* Another inaccuracy in the treatment of Orobanche in the New Manual may be 

 pointed out : Orobanche purpurea and O. ramosa are there characterized as having 

 "each flower with 3 bracts (1 large and 2 small) at the base of the calyx," O. minor 

 and O. ludoviciana as having "each flower with I or 2 bracts at the base of the 

 calyx,' ' and O. uniflora and O. fasciculata as being «' without bracts. ' ' The characters 



