Rydberg : Rocky Mountain flora 



63 



Epilobium latiusculum Rydb. sp. nov. 



Epilobium Drummondii latiusculum Rydb. Mem. N. Y. Bot. Gard. 



i: 276. 1900. 



To the characters given in the original description may be 

 added that the leaves are distinctly petioled, not sessile as in E. 

 Drummondii. 



Epilobium platyphyllum Rydb. sp. nov. 



Epilobium glaberrimum latifolium Barbey, Bot. Calif. 1 : 220. 1876. 



Not E. latifolium L. 1753. 



Epilobium paniculatum, as usually understood, contains several 

 forms or species, connecting on one hand with E. minutum, on the 

 other with E. jucundum. In order to facilitate the further study 

 of the groups, I give the following key of the Rocky Mountain 

 forms. 



Tube of the hypanthium funnelform, 1-3 mm. (rarely 4 mm.) 

 long. 

 Petals white only slightly exceeding the calyx, 2-3 mm. 

 long; capsule glabrous; tube of hypanthium 1-1.5 mm. 

 long. 

 Petals pink or purple, 3.5-7 mm. long, about twice as long 

 as the calyx. 

 Capsule and pedicels glabrous or sparingly puberulent. 

 Leaves and bracts very thick, horny at the apex, 

 the latter very short; capsule glabrous; pedicels 

 short. 

 Leaves and bracts not very thick, not horny at 

 the apex; capsule usually puberulent. at least 

 when young; pedicels slender. 

 Capsule and pedicels glandular-pubescent; pedicels 

 very short. 

 Tube of the hypanthium 4-8 mm. long, cylindric or nearly so, 

 abruptly widening into the calyx. 

 Tube of the hypanthium about 4 mm. long; petals 6-7 



mm. long. 

 Tube of the hypanthium 7-8 mm. long; petals 10-12 mm. 

 long. 



1. E. Tracvi. 



2. E. subulatum. 



3. E. paniculatum. 



4. E. adenodadum. 



5. E. laevicaule. 



6. E. Hammondii. 



Epilobium Tracyi Rydb. sp. nov. 



Annual; stem 3-8 dm. high, perfectly glabrous, straw-colored; 

 leaves 2-4 cm. long, linear, entire, glabrous; tube of the hypan- 

 thium 1-1.5 mm. long, funnelform; calyx-lobes about 2 mm. long, 

 very acute; petals white, 2-3 mm. long; capsule more or less 



