— 9 -- 
f. ]), judging from the scant material which I examined, I consider a good 
species. This view is also supported by the description of this species in 
DeNot. Epil. p. 606.” 
This historical review is of interest and indeed is essential to a right 
understanding of what I wish to say regarding a moss which has given me 
not a little trouble since I found it in April, 1901. It is th e Astomum sp.' 
mentioned in “Some Notes on Collecting” in the Bryologist 6 : March, 1903. 
In November last I found this same moss on the banks of the Mississippi, 
on Prairie Island, some three miles above Winona. This last collection 
included many with immature but well nourished and developed capsules, 
also quite a few fully ripe ones, full of spores. These ripe capsules showed 
clearly a tendency to a ring of modified cells separating the lid. In February 
1902 , 1 sent some of the plants collected on the bluff to Mr. Ernest Salmon, at 
the Kew Herbarium, to have a comparison made with Phascnm subexser- 
tum Hook. , the type of which I had reason to expect at Kew. Shortly after Mr. 
Salmon wrote that P. subexsertum Hook, cannot now be found. Meanwhile 
the discovery of a separable lid on the fresh material found, makes 
it clear that the plant is not a Phascum nor an Astomum but a Hymenosto - 
mum. I make it with considerable confidence close to, if not identical with, 
Hymenostomum rostellatum (Brid) Schimp. I reached this conclusion 
after a painstaking comparison of the plant with Limpricht’s description, 
Laubmoose, p. 224, 225, and with an Italian plant collected near Milan by 
Mr. F. A. Artaria. Size of spores, cells of exothecium, leaf areolation and 
shape, all agree perfectly. In both plants the lid separation is equally well 
indicated. Both lack however the crucial mark, the hymenium , whether on 
account of immaturity or for whatever other reason I cannot tell. 
Not satisfied that my Italian plants were typical H. rostellatum I sent 
the Minnesota plant to the New York Botanical Garden for comparison with 
typical European material if possible. Mrs. E. G. Britton very kindly com- 
pared the plants, not only favoring me with her judgment but she also sent 
me a plant or two of each, enough for comparison, of Astomum multicap- 
sulare , Systegium ( Astomum ) Ludovicianum Sulliv. , and No. 766 of 
Crypto. Gerv. des Fichtelgebirges, Phascum rostellatum Brid., collected by 
H. C. Funck. Mrs. Britton correctly points out that No. 766 has a somewhat 
longer beak than my plant but otherwise it is identical. I can however not 
agree that it is not near Systegium Ludovicianum which has the same 
leaves and spores of the same size exactly, but its beak is just a trifle 
shorter. The tendency to a separable lid is here also noticeable, and the convic- 
tion has grown on me that Systegium Ludovicianum and Hymenostomum 
rostellatum are practically identical, the beak being of somewhat variable 
length on the material of my own collections, approaching on the one hand 
the short beak on the single capsule I have seen of Drummond’s southern 
plant (New Orleans, 1841) communicated as Systegium Ludovicianum , and 
on the other hand the somewhat longer beaked plants from the Fichtelge- 
birge in Europe, the Italian plants holding in this respect the same middle 
place as my plants. It should be stated that so far as I could measure the 
