4 Muhlenbergia, Volume 5 



of reduced nutrition and moisture. We are well aware that a 

 reduced amount of leaf surface may take place from two dis- 

 tinctly opposite causes, one in the case of water plants because 

 the surface is not needed to secure food from the air, and the 

 other in the case of perennial desert plants where transpiration 

 must be reduced to the lowest possible amount on account of a 

 scarcity of water at the roots. 



We suggest that perhaps the shape of the leaf may be one 

 of nourishment, and hope to substantiate this by means of cul- 

 ture experiments. 



We were unable to find the difference in the shape of the 

 vexillum as indicated by House in his paper in Bot. Gaz. 41: 

 334 and 335. f. 1-2. 1906. The lower lateral edges naturally 

 double under at this point, and flatten out with much difficulty. 

 The vexillum in T. bifidum is the same as that shown for 7\ 

 Greenei \x\ f. /, but with a mucronate point. 



Our investigations therefore lead us to conclude that we 

 have but one species with many forms, none of which are suf- 

 ficiently separated by characters distinct enough to be described 

 as varieties. The description should be revised to include leaf- 

 lets from obovate and emarginate to bifid or deeply incised, 

 with a mucronate point between the lobes. The color of the 

 flower is the same in all, creamy, tinged with rose-pink. The 

 original description has "(annual?)" There is no doubt as to 

 the plant being an annual. The synonymy is as follows: 

 T. bifidum Gray, Proc. Cal. Acad. 3: 102. 1864. 



T. bifidum var. decipiens Greene, Fl. Fran. 24. 1S91; not 

 T. decipiens Hornem. Hort. Hafn. 2: 715. 1815. 



T. Hallii Howell, Fl. Northwest Am. 135. [898. 



'/'. Greenei House, Bot Gaz. 41 : 334. f. /. 1906. 



The following is the record of the leaflets shown on the 

 plate, the numbers indicating the specimens from which they 

 were taken: 



1-5 Silverton, Oregon, Hmvell rj2. 



6-10 Yamhill county, Washington, Henderson, July 8, 1882. 



11-15 inyon, Araquipa Hills, Solano county, Cali- 



fornia, Jepson, May 2-6, 1891. 



