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rower spores (11-18 X 4—5//) these commonly distinctly fusiform , and by the 
tendency of thelaciniae to become torulose. As in R. gracilis there is no 
reaction with potash. No American specimens of the R. rigida stock have 
yet been examined showing a medullary coloration on application of KHO, 
and it is certain that in Nylander's sense our southern examples must be 
referred to either R. gracilenta (Ach. ) Nyl. Mon. Ram. p. 19, or R. gracilis 
(Pers.) Nyl. 1 . c. p. 17. 
The so-called northern form of R. rigida that Willey in New Bedford 
Lichens thinks in its larger states may be referable to R. gracilenta has 
distinctly straight, ovoid or oblong-ellipsoid spores 8-15 X 4-6/* with the 
apothecia rather terminal than otherwise (in A’, rigida and its allies com- 
monly lateral). The form in no way resembles R. gracilenta and it is 
thought best to revive Tuckerman’s name of R. tenuis for its designation. 
Very similar forms are collected in Florida, showing that it is not exclu- 
sively northern, and the character cited by Tuckerman for his R. rigida , of 
“besprinkled often with white warts,” may only be applied to states of this 
species. , Rockland, Maine. 
NOTES ON THE FRUITING SEASON OF SOME OF THE MOSSES. 
Phebe M. Towle. 
Altho Dr. H. W. Arnell, of Upsala, Sweden, published, in 1875, a long 
list of the mosses of his country, giving their blooming and fruiting season 
and the time required for the development of their sporophytes, and Dr. A. 
Grimme brought out, in “ Hedwigia,” 1903, a similar list for Germany, yet, 
so far as the writer is aware, no extended list of this nature has been made 
for any part of America. 
Not only do the months for the blooming and the fruiting vary with the 
latitude and the climate, but the length of time required for the development 
also varies under differing conditions. So if a list should in time be made 
for Burlington, Vt., for instance, it would not wholly agree with a list made 
for a locality further south. In fact, in an instance to be mentioned later, the 
dates for northern Vermont do not agree with those for the region of New 
York City. 
Dr. Arnell, in The Bryologist for May, 1905, mentions the value of obser- 
vations repeated for several years for the sake of medium dates. The 
necessity for securing average dates has been emphasized by the late springs 
of 1906 and 1907, as compared with the early spring of 1905. In the latter 
year we had a warm April. But in 1906 on my first trip afield in the middle 
of April I found ice under the leaves on the slopes, and the flat was a sheet 
of ice. The first warm days began May 14th. 
In 1905 Mnium sylvaticum is recorded as shedding spores the latter half 
of April, while in 1906 the same species, in shady places in town, did not 
open their lids until May 16th, the third warm day. while Mnium affine ciliare 
was several days later. Altho the development of these mosses was delayed 
by the cold spring their blooming time was apparently not affected ; for the 
blooming time of both years was the same month — June, the 15th of the 
