138 RvDBERG : Rocky Mountain flora 



LIMNIA L. (Kongl. Sv. Vet. Ak. Hand. 1746: 130. 1746); 

 Haw. Syn. PI. Succ. 11. 18 12. 

 Greene, Howell and Robinson have transferred a number of 

 species from Claytonia to Ahvitia ; but none of them has given 

 any obvious reason. Dr. Greene satisfied himself by transferring 

 the sections Alsinastrum, Naiocrene and Montiastrum. These 

 evidently come nearest to Montia of all the sections of Claytonia. 

 Prof Howell, followed by Dr. Robinson, also transferred the sec- 

 tion Limnia, and the rhizomatous species of Euclaytonia of Gray. 

 The difference between the two genera Claytonia and Montia as 

 now limited is practically reduced to the number of ovules ; 6 in 

 the former, 3 in the latter. In Montia we find now both regular 

 and irregular flowers, free petals and partly united petals, 5 sta- 

 mens and 3 stamens, opposite stem-leaves and alternate stem- 

 leaves, annuals and perennials, and of the latter several kinds, viz., 

 with horizontal rootstocks, with short stolons bearing offsets, with 

 slender runners bearing cormlets at the ends, or with axillary bulb- 

 lets. In the olden time, Mo/itia was easily distinguished from 

 Claytonia by its gamopetalous corolla cleft on one side. It may be 

 that all the sections mentioned above should be removed from 

 Claytonia, but they should not be transferred to Montia, making 

 this genus more unnatural than Claytonia ever was. I think that 

 in a family like Portnlacaccac, in which the modifications in the 

 flowers are so slight, generic characters should to some degree 

 be sought in the general habit. Instead of transferring the sec- 

 tions to Montia it would have been better to restore the Linnaean 

 genus Limnia (which was adopted by Haworth), and to include in 

 it all the American species of Montia, except M. fontana ; or else 

 to continue the splitting and propose several new genera. The 

 typical Rocky Mountain species o{ Linniia are the following : 



Limnia asarifolia (Bong.) Rydb. 

 Claytonia asarifolia Bong. Veg. Sitcha 137. 183 I. 



Limnia sibirica (L.) Haw. Syn. PI. Succ. i i. 18 12. 

 Claytonia sibirica L. Sp. PI. 204. 1753. 



Limnia arenicola (Henderson) Rydb. 

 Claytonia arcniccla Henderson, Bull. Torrey Club 22 : 49. 1895. 



