January 3, 1910 1 59 



The impression seems to prevail in literature that T. longi- 

 bes has rather slender running roots and rootstoeks only, and 

 that all plants in the herbaria with long stout taproots must be- 

 long to some other species. We have given considerable atten- 

 tion to the root characters of this species in the field, and are 

 convinced that it has numerous slender running rootstoeks and 

 descending from these at irregular intervals long stout tap root-. 

 The collector, unless especially studying the root characters, will 

 dig down a few inches and bring up the small roots and root- 

 stocks only. 



The species also varies very greatly in regard to the form 

 of the leaflets and other characters, depending upon the condi- 

 tions under which it is growing: 



1. (See//, j.f. 1-2.) If the soil is sandy and sterile and 

 the plant in the shade, the leaflets, stems and peduncles are very 

 slender. 



2. (Seep/. 7. f. j.) If growing in irrigated meadows, cut 

 for hay along with native blue grasses and sedges, the lower 

 elliptical and semi-orbicular leaflets are smothered and the upper 

 ovate-lanceolate, either acute or obtuse ones are well developed. 



3. (See/>/. 7. f. /.) If in gravelly soil with plenty of room 

 and exposed to conditions of drought during the hot summer 

 months, the plants are strongly pubescent and the upper leaves 

 narrower, but an abundance of short petioled semi-orbicular leaf- 

 lets at the base. This form has been mistaken for T. Rusbyi, 

 but the flowers have very short pedicels and do not reflex in age. 



4. (See//, j.f. ^-6.) These plants were collected and stud- 

 ied within a few yards of one another, and undoubtedly repre- 

 sent the same species. The smaller ones {/. j.) were dug out of 

 sod in a meadow which is grazed severely by sheep every sea- 

 son, and where the water level is close to the surface for the 

 greater part of the year, preventing the descent of the long tap 

 root, as we find it here short and thick. The leaflets in some 

 of the plants were narrow and some broad, apparently under the 

 same conditions. Likewise the flowers varied from while, white 

 shaded with light purple, to purple and red. 



