EXPERIMENT STATION BULLETINS. 253 



flowers, a few on each small peduncle, fruits very small, few seeded, the growth 

 dense and mattted. 



V. disperma, D. C. Flowers July 7 to September 27, matted growth 3G inches 

 high August 19, fruit not abundant but a very large quantity of succulent 

 green matter. 



V. argigentinum, Guss. ^= Y. Mvonea, Rafin. Flowers July IC, fruit August 

 19, growth 32 inches; does not fruit freely but produces a large bulk of green 

 material. 



T'. liirsuta, S. F. Gray. Minute flowers July 8, flowers and fruit August 19 to 

 September 27, 21 inches high August 19. This species fruits freely but produces 

 less growth than the preceding. 



The following vetches have abundant, showy, red, purple or blue flowers, one 

 sided on long peduncles; rampant leafy vines, forming a tangled mass. They 

 are given in the order of their growth, the largest first. Few of them fruited 

 freely. 



V. biennis, Linn. Flowers June 21 to September 27, 48 inches high August 19. 



y. ludoviciana, Nutt. Flowers July 16 to September 27, 3G inches high August 

 IG. This species gives a thick, heavy, dense mass of vegetation over the entire 

 plot. 



V. gerardii, Vill. Flowers before July 7 and until September 27, showy blue 

 flowers, 36 inches high August 19. 



y. glotosa, Retz. Red flowers June 21 to September 27, young fruit August 

 19, 35 inches high August 19. 



y. narbonensis, Linn. Planted June 22, too late to compare with the other 

 varieties and species. Its dark red flowers were conspicuous July 29 through the 

 season to September 27. Its fruit was nearly ripe September 27. 



The vetch known as horse bean, V. faba, Linn., has been grown annually but 

 is unsuited to Michigan climate and conditions. It is regularly attacked by 

 plant lice and practically killed. 



While many of the vetches resemble each other closely others vary widely in 

 appearance. Prof. B. O. Longyear, then botanist of the station, made a some- 

 what careful study of the botanical characteristics of the species of vetches grow- 

 ing on the station plots and suggested the following analytical key as an aid 

 in discriminating between the several species. This key is confessedly tentative 

 but will aid in placing a new vetch in proper relation to known forms. 



ANAI.YTICAI, KEY TO VETCHES. 



I. Stems erect, stout; leaflets large, few tendrils poorly developed; whole 

 plant glabrous, becoming blackened where dried. 



y. sativa dura. 



V. faba. 



y. narbonensis. 



II. Stems spreading or climbing; slender; leaflets mostly small and num- 

 erous; tendrils well developed; plant more or less hairy or pubescent. 



A. Stipules, especially the lower, with several prongs, with a reddish glandu- 

 lar spot; leaflets numerous, truncate or notched, mucronate; flowers 1-3, sessile 

 or short stalked in axils of leaves, purple. 



a. Stems and pods velvety, more or less robust; flowers three-fourths to one 



inch long. 



1. Pods one-half inch or more wide, robust, Y. sativa typica. 



2. Pods one-third inch wide, Y. peregrina. • 



3. Pods one-fourth inch wide, Y. cornigera. 



(These three species form a descending scale as regards size and hairiness 

 w'ith y. Sativa typica standing at the head.) 



b. Mostly slender, sparingly pubescent; flowers usually less than three- 



fourths inch long. 



1. Leaflets mostly obtuse-truncate at apex, Y. grandiflora. 

 Leaflets oblong-linear, Y. angustifolia. 



Stipules large, margin lacerated, Y. canadensis. , 



2. Leaflets mostly refuse or notched at apex. 



*Stems and pods minutely pubescent, Y. segetalis, Y. ambigua (deeply 



notched). 

 **Steins and pods nearly or quite glabrous, Y. picta, Y. Calcarata, Y. 



cordata. 



