—70— 
cells,' more pigmented orange to purplish, as contrasted with the normal brown 
of A. crispum. The operculum of A. Sullivantii is never separated off, while that 
of A. crispum, though varying somewhat in this respect, tends to be well marked 
off, or even in extreme cases separable. These differential characters are perhaps 
not wholly convincing, but as they seem to fairly consistently separate the 
plants of two rather remote areas they may, I think, be safely regarded as 
justifying the treatment of the American plant as a distinct species, though I 
have no especial quarrel with anyone preferring to call them marked geographical 
varieties of a single species. Characters of the gametophyte in these plants 
are elusive, not to say illusive, and appear to add nothing in this case, except the 
generally somewhat coarser manner of growth of the European species. The 
American species is by no means without variation and in fact runs through 
a series of forms that are often parallel to those European ones which have been 
treated as independent species. Mrs. Britton had for example in her earlier 
study of the genus segregated a number of specimens from our northeastern 
states, which she called Astonium multicapsulare (Sm.) Br. & Sch.* This form 
is distinguished by an elongated stem, even up to an inch or more in height and 
collapse of the weak cells between it and the spore-sac, a single layer of thin cells usually appearing 
in section. This character however like others is not an absolute one, as occasional American 
specimens show a somewhat thicker wall, but is not without significance in the aggregate of 
features. It is perhaps of passing interest to note that the type of A. Levieri Limpricht of southern 
Europe, a bit of which I owe to the kindness of the late Georg Roth, shows a very thin capsule- 
wall, as in fact noted by Limpricht in his original description (Rabenhorst.Kryptogamentlora, 
IV, iii. 638. 1901), though the plant shows otherwise no close relation to our species. 
7 The individual cells vary so much in size and shape that it is not easy to establish a basis 
of comparison, but it is certainly true that with a decidely smaller capsule the North American 
species has slightly larger, or at least broader, exothecial cells than the European. The striking 
impression is that of the small number of exothecial cells to the capsule in the American species. 
The European shows a greater tendency to have the exothecial cells longer than wide, that is, 
lengthened in the longitudinal direction of the capsule, another mark of the less cleistocarpous, 
more advanced species. 
8 It is not my intention to express any opinion on European species, except as is rendered 
necessary by the interpretation of our own forms, but I would call attention to the fact that 
the name of A. multicapsulare is not wholly satisfactorily founded. It has been noted that it 
does not especially apply, as it generally bears but a single capsule (Dixon, Student's Handbook 
of British Mosses, 206. 1896; Bruch & Schimper, Bryologia Europaea, Monograph Astomum, 4. 
1850). Smith's Phascum multicapsulare (Flora Brittanica, 1152. 1804) is based on specimens 
collected by Chas. Abbot and cites the latter 's P. sphaerocarpon (Flora Bedfordiensis, 230.1798) 
as a synonym, also the P. crispum of Swartz' Muse. Suec, 17 and the plate No. 618 in English 
Botany. This plate (Smith, English Botany, ix. 1799) is from Bedfordshire specimens discovered 
in March, 1799 by Abbot. The plate is labeled P. crispum and appears to me to represent that 
species, though I may be in error. Anyhow, if P. multicapsulare is not P. crispum or a mixture, 
it is only a later synonym of P. sphaerocarpon, which should as the prior name be restored. Ac- 
cording to Smith, Abbot collected P. crispum as well as P. multicapsulare near Bedford. 
I note also an Astomum intermedium Peterfi, which appears to have found no place in European 
bibliography. It is referred to by its author in a reprint from the Mathematische und natur- 
wissenschaftliche Berichte aus Ungarn, xix, 356, which appears to be a German translation 
from the Potfiizetek a Termeszettudumanyi Kozlonyhoz, lxi, 143, Budapest, 190 1, the ori- 
ginal publication of the species being in Lii, 108 of this latter series. 
