1902] Fernald, — Variations of American Cranberries 235 



its characteristic form from the Small Cranberry, V. Oxycoccus. 

 Usually V. macrocarpon is a coarser plant with larger obtuse veiny 

 leaves which are pale but not whitened beneath and with very slightly 

 revolute margin, and the pedicels of the larger flowers and fruits are 

 produced upon an elongated rachis from the tip of which arises a 

 leafy shoot. V. Oxycoccus on the other hand, in its typical form, 

 has almost capillary steins, and the leaves are smaller than in V. 

 macrocarpon, whitened beneath and so conspicuously revolute above 

 the middle as to produce a narrow triangular acute-tipped outline. 

 The flowers and fruits are smaller than in V. macrocarpon and the 

 pedicels ordinarily arise from a very short terminal axis or rachis, 

 although in rare individuals the rachis is elongated and proliferous 

 as in V. macrocarpon. The flowers of the two species also present 

 differential characters, the larger flowers of V. macrocarpon having the 

 anthers proportionately longer than in smaller flowers of V. Oxycoccus. 

 But although the typical forms of Vaccinium macrocarpon and V. 

 Oxycoccus are clearly enough distinguished by their ordinarily defined 

 characters, a third plant of New England has proved more puzzling. 

 V. macrocarpon is confined for the most part to grassy swamps or 

 sandy bogs of the coastal plain or to wet shores at low altitudes 

 inland, while V. Oxycoccus, at least in New England and eastern Can- 

 ada, is a plant of cold sphagnum bogs or of humus. The third cran- 

 berry which has recently attracted the attention of New England 

 botanists grows like V. Oxycoccus in sphagnum bogs, but superficially 

 it seems exactly intermediate between that and the larger species of 

 the warmer swamps. The stems are quite as coarse as in small 

 plants of V. macrocarpon, the leaves, much larger than in V. Oxycoc- 

 cus, are only slightly revolute and often quite obtuse at tip, the flow- 

 ers and fruit are larger, though small for V. macrocarpon, and the 

 rachis shows a decided tendency to proliferation. 1 



On account of its somewhat intermediate characters this larger 

 plant of the New England sphagnum bogs has been thought to rep- 

 resent a transition between the two well-known species, or perhaps 

 to be of hybrid origin. The latter origin of the plant is, however, 

 quite improbable since in northern Maine it is abundant in swamps 

 far outside the range of V. macrocarpon, and, furthermore, the inter- 

 mediate plant is exactly matched by material from eastern Asia and 



1 Of 64 inflorescences examined, 27 (or .42) show more or less proliferation, 

 of 90 inflorescences of V. Oxycoccus 18 (or .20) show proliferation, while of 140 

 inflorescences of V. macrocarpon 132 (or .94) exhibit this characteristic. 



