210 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



16. Viola triloba Schwein. 



Dry or moist woods; frequent. Apr-May. New Eng. to Ga. { V. palmata oi Bome 

 authors, not of Linnaeus; V. vespertilionis Greene; V. omithodes Greene.) 



V. omithodes was described from plants growing in Rock Creek Park; V. vespertil- 

 ionis from specimens from Brookland. 



16. Viola sororia Willd. Downy violet. 

 Moist meadows or banks or in rather dry woods; frequent along the Potomac, infre- 

 quent elsewhere. Apr .-May. Northern states, south to N. C. (V. laetecaerulea 

 Greene.) 



17. Viola hirsutula Brainerd. 



Dry fields or hillsides, commonly in pine woods; frequent. Apr .-May. N. Y to 

 Ga. ( V. villosa of many authors, not of Walter; V. cucullata cordata of Ward's Flora.) 



Viola hirsutula X sororia Dowell. 



Naucks and Hyattsville. Leaves in outline similar to those of V. sororia, larger 

 than those of V. hirsutula, with the characteristic pubescence of the latter. 



Viola hirsutula X stoneana Brainerd. 



Hyattsville. Leaves lobed much as in V. stoneana, but less deeply, with the pubes- 

 cence of V. hirsutula. (F. stoneana X w'Wosa House.) 



Viola hirsutula X triloba Brainerd. 



Glen Sligo. Leaves with the pubescence of V. hirsutula; lobed as in V. triloba, or 

 some of them only coarsely toothed. 



18. Viola cucullata Ait. 



Along streams and in bogs; frequent. Apr.-May. Eastern N. Amer. ( V. macrotis 

 Greene; F./ontona Greene.) 



The type of F. macrotis is from Surrattsville ; that of V.fontana was collected along 

 Rock Creek just outside the District. 

 Viola cucullata X papilionacea Brainerd. 



Collected at several stations. In general characters almost intermediate between 

 the parents. 



A plant from Hyattsville was reported by House as F. cucullata X emarginata Brain- 

 erd. The writer has not seen the specimens. The Long Island plant (F. lavandu- 

 lacea Bicknell) to which this interpretation was given is now believed to be F. cuxul- 

 lata X primulifolia. The Hyattsville plant is considered a true hybrid between 

 F. cucullata and F. emarginata. 



19. Viola affinis Le Conte. Slender violet. 

 Moist meadows and woods; common. Apr.-May. Eastern U. S. (F. nepetaefolia 



Greene.) 

 The type of F. nepetaefolia was collected beyond Anacostia. 



Viola affinis X cucullata Brainerd. 



At several stations north of Washington. Differing from F. affinis in the larger 

 leaves, long slender cleistogamous flowers, and long-auricled sepals; from F. cucullata 

 in the very acute leaves and brown-dotted capsules. 

 Viola affinis X hirsutula Brainerd. 



Several scattered stations. Leaves in outline like those of F. affinis, with the 

 pubescence of V. hirsutula. ( F. affinis X villosa Brainerd.) 

 Viola affinis X papilionacea House. 



Widely distributed in our region; the type from Woodridge. Leaves larger than 

 those of F. affinis, but usually resembling them in shape and texture; flower and fruit 

 characters intermediate between those of the parents. ( F. filicetorum Greene.) 



F. filicetorum was based upon material from our region. 

 Viola affinis X sagittata Brainerd. 



Patuxent. Leaves intermediate between those of the two parents ; capsiiles minutely 

 pubescent as in F. affinis. 



