150 Rhodora [JuLy 
other hand, the teeth are much longer and as a rule a much greater 
portion of the tooth-producing cell protrudes; in many cases, in fact, 
almost the entire cell projects outward in the form of a tooth, and fre- 
quently the whole upper half of the leaf is little more than an excurrent 
midrib from which long teeth project in all directions. Æ. papillosum 
differs from the two species above mentioned in its broader, much more 
papillose leaves, and in the structure of its calyptra which is rendered 
markedly papillose by the projection of the outer walls of its cells. 
According to Austin’s description t the leaves of E. papillosum are 
narrower than those of E. crassinervium but an examination of Austin’s 
specimens of both species has failed to verify this observation. The 
character of the leaf margin is intermediate between that of E. crassi- 
nervium and E. spinulosum. 
The revised list of Ephemerum species found in Connecticut is here 
given. 
. megalosporum: Orange (Evans, 1891). 
. cohaerens: East Haven (Evans, 1891), New Haven (G. E. N.). 
. erassinervium: Branford (G. E. N., 1909). 
. papillosum: New Haven and North Haven (G. E. N., 1909). 
spinulosum: Hartford (Miss Lorenz), East Haven (Evans), 
New Haven (G. E. N.), Orange (J. A. Allen, 1879), Oxford 
(Harger), Portland (G. E. N.), and Norwich (Setchell). 
For the sake of convenience the diagnostic characters of these five 
species are summed up in the following key. 
b lv wbowaMidb.... .....'€7.5 01. 9 —- 
Midrib present, although often indistinct . . . . . . . . . . 
2. Leaves obseurely serrulate; stomata present in upper half of capsule 
E. megalosporum. 
Leaves strongly serrate; stomata restricted to base of capsule. 
E. serratum. 
3. Leaves ovate-lanceolate, smooth except on the midrib . E. cohaerens. 
Leaves narrowly lanceolate, distinctly papillose 
4. Calyptra conspicuously papillose E i 
Calyptra smooth or nearly so Vi 2. e he de MEER DET d TO 
5. Teeth in apical half of leaves usually short . . . . E.crassinervium. 
Teeth in apical half of leaves usually long . . . . E. spinulosum. 
E. papillosum. 
5 
The writer is about to undertake a revision of the North American 
species of Nanomitrium and Ephemerum, and a considerable amount 
of material for study is already at hand. Since, however, it is desired 
to make the work as thorough and comprehensive as possible, it will be 
greatly appreciated if American bryologists will cooperate through the 
loan or exchange of specimens. 
1 Musci Appal. Exsic. No. 50. 1870. 
