1912] Evans,— Notes on New England Hepaticae,— IX 3 
The species is monoicous, and the capsules, which are abundantly 
produced, are irregularly scattered along the median portion of the 
thallus. At maturity they can readily be seen through the trans- 
lucent tissues as a series of dark spots, and when the plants become 
dry the capsules protrude above the upper surface. The spores are 
dark brown and average about 85 u in diameter. All four faces are 
clearly reticulated, and a distinct wing 5-10 u wide is developed at 
the junction between the convex face and the three plane faces. The 
wing is yellowish brown and crispate, the margin being more or less 
crenulate and the surface minutely verruculose. On the convex 
face of the spore there are about eight meshes across the diameter, 
and the meshes measure about 10 uw in width. In profile view the 
ridges which bound the meshes appear low but project at the angles 
of the meshes as truncate points, perhaps 5 u in length. The plane 
faces have lower ridges than the convex face but are otherwise much 
the same. 
There seems to be little to distinguish R. arvensis from the European 
plant which is now usually known as R. bifurca Hoffm. This species 
was published in 1795,! but the original description is very incomplete 
and would apply equally well to a number of distinct plants. The 
type material is apparently no longer in existence. For these reasons 
the name R. bifurca, although it continued to be used by authors, had 
no definite signification until the end of the last century. As late 
as 1892 Camus,? in reviewing what was known about the species, 
pronounced it very badly understood and even hypothetical. It was 
not until 1898, when the subject was investigated by Heeg,’ that the 
species became defined in its present sense. He based his conclusions 
upon the specimens which Lindenberg,‘ in 1836, referred to R. bifurca, 
but unfortunately even these specimens did aot lead to definite results. 
In the fascicle labeled R. bifurca, Heeg found four distinct species and 
simply selected the one which seemed to him to coincide best with 
Lindenberg’s description and figures. He reserved the name for 
this particular species and referred to R. bifurca, as thus restricted, 
a number of specimens from various localities in Sweden, Switzerland, 
and Austria. These he described clearly and fully. His conclusions 
1 Deutschlands Flora 2: 95. 1795. 
? Bull. Soc. Bot. France 39: 229. 1892. 
3 Bot. Not. 1898: 107. 
4 Nova Acta Acad. Caes. Leop. Carol. 18: 425. pl. 20, f. 1. 1836. 
