\\IIH MuUlk- ..I \l \\ \ORK 171 



of various crosses of V i o 1 a tricolor with allied species of the 

 Old World. In addition to those, then- arv alxmt thirty-thnv native 

 species of violets in NY\v York. IXM<U- tin- many natural hybrids. The 

 following ki-y to tin- nativr sjxru-s may IK- useful in determining certain 

 species not illustrated here. 



i Stemles-;. tlu- leaves and scapes directly from a rootstock or from runners 



Petals bright yellow; leaves orbicular. i V r o t u n d i f o I i a 



Petals violet, purple or white 



rieisiogamous flowers wanting; petals all beardless; leaves divi<lel 



i V pedal a 

 Clcisti famous flowers present, at least later in the season 



Rootstock thick, often Mut. without stolons; lateral petals bearded 



(.'loistoKamous fl<> <1 on short prostrate peduncles; their capsules 



mostly purplish 

 Leaves except rarely the earliest, palmatcly five- to cleven-lobed 



or parted, foliage villous-pubescent 



Lcaf-l.iU-s Munt. lateral ones broad 3 V. pal mat a 



Leaf-lobes acuminate, lateral ones linear. 4\' perpensa 



Early and late leaves uncut, others three- to seven-lobed or parted 



; V t r 1 1 o b a 

 Leaves all uncut; hlade-i ovate 'rm. cordate, crenate- 



serrate 

 Plants nearly or quite glabrous; petab violet-purple; seeds 



1 >r< >wn 

 Petioles smooth ; plants of moist soil 



6V. papilionacea 

 Petioles glandular roughened; plants of dry soil 



; V latiuscula 



Leaves very hairy, especially beneath and on the petioles; 

 seeds dark bn.wn JV. sororia 



Leaves hirsutulous above, otherwise smooth; seeds buff. 



Q V. hirsutula 

 Cleistogamous flowers ovoid on ascending peduncles, soon elonga- 



.ul-i-sct-nt iH-neath and on the petioles; sepals and their 

 auricles ciliolate; blades broadly ovate, cordate 



10 V. septentrional is 



