462 Rydberg: Notes on Philotria Raf. 



oblong leaves, and the bifid, instead of emarginate, stigmas. Cas- 

 pary includes herein also the specimens collected at St. Louis, Mo., 

 and distributed as Udora verticillata? minor Engelm., but this 1 

 believe to be distinct. See below. 

 Anacharis canadensis Planch. Ann. Sci. Nat. Bot. III. n : 75. 



1 849. 



Planchon's description differs considerably from that of 



Michaux and he could not have had the same plant in mind. 

 The plant is said to be dioecious, the spathe of the staminate 

 flowers ventricose-obovate and short-peduncled, and the staminate 

 flowers themselves apetalous. It was described from staminate 

 specimens collected by Drummond in Saskatchewan and imper- 

 fect pistillate specimens from Canada collected by Cleghorn. 

 There is no evidence that the two belonged to the same species, 

 but the staminate plants of Drummond must be regarded as the 

 type. On these was based 

 Elodea Planchonii Casp., Jahrb. Wiss. Bot. 1 : 468. 1858. 



This is evidently a very distinct species and unique in the two 

 characters given. The staminate flowers are much larger than 

 in the other North American species, but the pistillate ones are as 

 small as those of Philotria minor Small {Udora verticillata minor 

 Engelm.). The leaves are usually as narrow as in that species, 

 and in Philotria angustifolia (Muhl.) Britton. In my Flora of 

 Colorado I referred the specimens of that state to those species. 

 Having discovered my mistake, I shall here give a fuller descnp- 

 tion of the plant : 



Philotria Planchonii (Casp.) Rydb. 



Dioecious water-plant ; stem slender, 1-5 cm. long ; leaves in 3 

 or the lower opposite, 7-15 mm. long, oblong to lance-Imea, 

 acutish ; spathe of the staminate flowers obovoid-clavate, neary 

 1 cm. long, on a peduncle 5-10 mm. long ; flowers short-pedice e , 

 sepals elliptic, 5 mm. long ; petals lacking ; stamens 9 



nthers 

 lant 



oblong, 3-4 mm. long, subsessile ; spathe of the pistillate p 

 linear or lance-linear, sessile, 2- cleft at the apex; calyx- 



linear or lance-linear, sessile, 2- cleft at the apex; 

 slender, 3-5 



styles 3, linear ; stamens none. 



Al 



The following specimens belong here : Seven Mile Lakes, * 



N. Gooding 3 g7 



staminate 



