886 



Caprifoliaceae 



Triosteum 



Map 1944 

 Triosteum perfohatum L 



50 



Map 1945 



Triosteum aurantiacum Bickn 



— ~3o 



Map 1946 



Triosteum aurantiacum var illinoense 

 (Wieg) Palmer & Steyermark 



Wiegand places this species as a variety of the preceding one on the 

 basis that there are intergrading plants and some plants of the non- 

 perfoliate group are sometimes perfoliate and sometimes the pubescence 

 characters are not constant. It has been observed that, as is shown in 

 Bicknell's description, the leaves of T. aurantiacum, are sometimes perfoli- 

 ate but it is true only of the upper ones, not the middle or principal leaves, 

 while in T. perfoliatum, it is the middle leaves which are perfoliate and if 

 there is any difference in the leaves, it is the upper ones which are nar- 

 rowed. The fruit characters, however, their color, shape, and pubescence, 

 the time of flowering and maturing of fruit, and various other combina- 

 tions of characters are sufficient to separate the two without depending 

 upon the types of leaves although they are helpful when understood. 



Que. to Conn., and in the mts. to Va., and from N. Y. to 111. and Wis. 



2a. Triosteum aurantiacum var. illinoense (Wieg.) Palmer & Steyer- 

 mark. (Rhodora 40: 133. 1938.) Map 1946. This variety occurs through- 

 out the state. Nearly all of our specimens are from rocky, wooded slopes 

 bordering streams. A few are from dry woods. The pubescence of the 

 fruit, stem, and leaves is longer than that in the species. 



Ohio to Mo. 



2b. Triosteum aurantiacum var. glaucescens Wieg. (Rhodora 20: 116. 

 1918.) Map 1947. Our only specimen is from the wooded bank of Raccoon 

 Creek south of Russellville, Putnam County. Both surfaces of the leaves 

 are entirely glabrous ; the pubescence of the stem is as in T. aurantiacum. 



Cent. N. Y. to Pa. and Ind. 



3. Triosteum angustifolium L. YELLOW-FLOWER Horsegentian. Map 

 1948. This species is undoubtedly restricted to the southern half of the 

 state. I have found it on dry, wooded slopes only, and usually associated 

 with black and white oak. 



Conn, to Md., and in the uplands to Ala. and Tenn., westw. to 111. and Mo. 



