120 THE AZALEAS OF NORTH AMERICA 



lar-pilose but otherwise glabrous ovary, hirsute branchlets and hirsute large obo- 

 vate leaves, a very thin-valved oblong-ovoid capsule almost destitute of glands at 

 maturity; its flowers appear after the full development of the leaves, while in all 

 the other species of this group they open before the leaves unfold. The petiole 

 of the shoot-leaves in R. Vaseyi, R. nipponicum and R. Albrechtii is somewhat de- 

 current on the stem, leaving an elongated scar distinctly longer than broad. 



In the section Rhodora I have included R. Vaseyi as suggested by Gray and 

 as done by Dippel and by Koehne; by Small this has been made the type of a new 

 genus Biltia, chiefly distinguished by the exterior aestivation of the middle lobe of 

 the upper lip of the corolla. This position of the posterior lobe is without doubt 

 unusual in the genus, but can be observed at least occasionally in species related 

 to R. Vaseyi. Among flowers of R. canadense I have found a small percentage 

 with the middle lobe of the upper Up exterior and in R. Schlippenbachii, which 

 belongs to the section nearest to Rhodora and is very similar in its flowers to 

 R. Albrechtii and R. quinquefolium, both closely related to R. Vaseyi, I have found 

 after examining numerous fresh flowers just before opening that about 15 per cent 

 of the flowers had the middle lobe of the upper lip completely exterior and 25 to 

 30 per cent had one side exterior and the other side covered. This shows that the 

 position of the upper lobe cannot be used as a reliable character to separate Biltia 

 generically. As there is no other character to separate R. Vaseyi from the other 

 species of the section Rhodora except the number of stamens, which also cannot 

 be considered a reliable character in the genus Rhododendron, it seems best to 

 retain it in this section. 



Rhododendron canadense Torrey, Cat. PL 151 (in Geol. Surv. New 

 York Assembly, No. 50) (1839). Oakes, Cat. Vermont PL 190 (in 

 Thompson, Hist. Vermont) (1842). Wood, Classb. Bot. 235 (1845). 

 Zabel, Syst. Verz. Muenden, 26 (1878). Britton, Sterns, Poggenburg, 

 Prelim. Cat. New York, 33 (1888). Britton, Cat. PL N. Jersey, 162 

 (1889). Dippel, Handb. Laubhokk. I. 418 (1889). Robinson & 

 Fernald, Gray's New Man. ed. 7, 631 (1908). Schneider, III. Handb. 

 Laubholzk. I. 494, fig. 327 i-k, 328 f (1909). Jackson, Cat. FL Worces- 

 ter Co., Mass. 76 (1909). Graves & others, Cat. Flow. PL Conn. 308 

 (1910). Twining, FL N. E. Pennsylv. 56 (1917). 



Rhodora canadensis Linnaeus, Spec. ed. 2, 561 (1762). Willdenow, Spec. I. 

 pt. 2, 866 (1798). Michaux, FL Bor.-Am. I. 259 (1803). Pursh, FL Am. 

 Sept. I. 298 (1814). Bigelow, FL Boston, 104 (1814). De Candolle, 

 Prodr. VII. 719 (1839). Gray, Man. 267 (1848); ed. 5, 309 (1867). 

 Tracy, Stud. Essex FL 49 (1858). Britton & Brown, III. FL 560, fig. 2748 

 (1897). Clute, FL Upp. Susquehanna, 70 (1898). Britton, Man. 699 

 (1901). Small, Fl. Pennsylv. 238 (1903); in N. Am. FL XXIX. 44 (1914). 



Hochenwartia canadensis Crantz, Inst. II. 469 (1766). 



Rhododendron Rhodora G. F. Gmelin, Syst. Nat. II. pt. 1, 694 (1791). 

 Sweet, Hort. Brit. ed. 2, 343 (1830). G. Don, Gen. Syst. III. 848 (1834). 

 Gray, Syn. FL II. 1, 41 (1878). J. Robinson, FL Essex Co., Mass. 73 

 (1880). Macoun, Cat. Canad. PL II. 302 (1884). Dame & Collins, FL 

 Middlesex Co., Mass. 63 (1888). Perkins, Cat. FL Vermont, 33 (1888). 

 Bennett, PL Rhode Isl. 26 (1888). Coulter & Watson, Gray's Man. 

 ed. 6, 321 (1890). Rand & Redfield, FL Mt. Desert Isl. 127 (1894). 



