236 Rhodora [Decmw* 



northwestern America where no V. macrocarpon is known to occur. 

 This Pacific coast form, nevertheless, was taken by Sir William 

 Hooker for the larger eastern species for he states 1 that at the mouth 

 of the Columbia V. macrocarpon is very abundant. Later, however, 

 Dr. Gray in studying the Vacciniums considered the Pacific slope 

 cranberry best treated as a large variety of V. Oxycoccus, 



The material now at hand shows that this intermediate form, V. 

 Oxycoccus, var. intermedium. Gray, is not confined to northwestern 

 America and eastern Asia as originally supposed by Dr. Gray, 

 but that as already stated it is in the upland bogs of New England. 

 In fact many specimens previously referred on account of their size 

 to V, macrocarpon have the more pointed foliage and the characters 

 of inflorescence of V. Oxycoccus, var. intermedium. To this form 

 belongs the Saskatchewan material of Pourgeau formerly referred to 

 /'. macrocarfon, a species which apparently reaches inland only to the 

 Great Lakes. 



The characters — size of plant, size and outline of leaf, size of 

 fiower and fruit and proliferation of the dowering rachis — ordinarily 

 relied upon to separate the circumboreal Vaccinium Oxycoccus and 

 the strictly American /". macrocarpon are so mingled in V. Oxycoccus, 

 var. intermedium as to render their use as final criteria too mislead- 

 ing. But another character apparently overlooked by students of the 

 "roup very materially reinforces the traditional ones. In V. macro- 

 carpon, with the dowers borne on a proliferous rachis, the pedicels 

 bear, usually toward their tips, a pair of subapproximate leafdike 

 bracts. Ordinarily these bracts are 4 or 5 mm. long, green and of 

 firm texture, but occasionally they become nearly or quite twice that 

 size. In the smaller V. Oxy coccus, with the dowers on a short 

 terminal rachis which is rarely proliferous, the pedicels bear, usually 

 near or below their middle, a pair of lanceolate or lance-ovate 

 often strongly involute colored bracts 1 to 2.5 mm. long. In the 

 larger plant of the northwest, now found to occur likewise in the east, 

 the bracts are exactly those of V, Oxycoccus, and, in view of its leaves 



with more whitened under surface, its ordinarily terminal indores- 



cence and its range, it is undoubtedly a very large development of 



V, Oxycoccus, 

 The three true Cranberries may be readily recognized by the 



following characters : 



1 I look. I']. Bor.-Am. ii. )v 



