BRAGHYTHECIUM NOTES 
A. J. Grout 
Brachythecium pacificum (^R. &. C.) Grout 
B. reflexum pacificum R. & C, Bot. Centralb. 1890, No. 51. Not B. paci- 
ficum Jennings, Bryologist 16: 95, Nov. 1913.* 
Up to the year 1919 I had confused this moss with B. glaciate B. & S. Others 
here and abroad had confused it with B. reflexum (Starke) B. & S. and B. Starktt 
(Brid.) B. & S. The onl> North American plant that I have seen that seems re- 
ferable to B. glacials is Macoun's Canadian Musci No. 735a, from earth and rocks, 
Cape Breton Id., Nova Scotia, July 8, i8q8. 
This group, including B. reflexum, B. glaciale, B. Sfarkei and B. pacificum, 
has puzzled bryologists for a long time, not only in America but also in Europe. 
Part of my bewilderment is attributable to a specimen from Greenland, ex-herb. 
Schimper, communicated by Cardot, as B. glaciale, which is not that species, but 
a very robust form of reflexum approaching pactficum, or, possibly, it may be 
near the var. micropus (B. micropus B. & S.). 
Although I have not studied the calyptra and peristome of these forms from 
North America, forms of B. reflexum approaching micropus in gametophyte 
characters are not rare in North America. The> rin larger in size and have the 
leaves less abruptly acuminate, with leaf-cells longer and narrower. 
B. Starkei is the most robust of the group, with leaves spreading, scarcely pli- 
cate, often almost complanate, very widely cordate-ovate. B. glaciale is more 
slender, julaceus, with leaves appressed, somewhat plicate, with the costa per- 
haps averaging a little longer than in B. Siarkei, but this is not constant. 
B. pacificum is much more slender than B. glaciale, approaching B. reflexum 
in habit, but with leaves less closely appressed when dry, costa longer and stron- 
ger than in Starkei or glaciale, but not consistently percurrent. Leaf-cells much 
like those of Starkd in outline, but smaller. 
B. reflexum is typically very slender, almost filiform, with widely cordate- 
ovate leaves, abruptly long-acuminate, leaf-cells much as in the shorter-celled 
Amhlystegia, typically about 5 : i in the stem-leaves. 
According to Braithwaite, Bottini considers B. refiexum micropus a hybrid 
with B. populeum. There is much to suggest hybrids in the varying and inter- 
grading species of this group. B. Siarkei and B. reflexum are common in the 
mountain regions of North America, apparently less frequent westward. I have 
B. pacificum from Norway, communicated b> Holzinger (See Mosses of the Soils 
Kelp Expedition, Holzinger and Frve. Publications of the Puget Sound Biolog- 
* Dr. Jennings has very kindly sent me a part of his type of Brachythecium pacificum Jennings, 
I. c. After a careful comparison with slides of the type of B. asperrtmum Mitt., I feel sure that 
the two are the same species. The serration of ihe Icav^es is not materially different, in spite of 
the differences in descriptions. B. asperrtmum is dioicous and Jennings reports no antheridia on 
his fruiting plants. Had Jennings' material come to me unnamed, I should ^have referred it to 
aspernmum without the slightest ht^sitation. 
