— IO — 
long, i mm. broad, margins plain, entire; costa strong, ioo ju thick at base, 
vanishing far above the middle, areolation lax, cells 60-80/* long, 12/* broad, 
walls thin and soft. Other characters unknown. Plate XXV. 
Missouri. Monteer, in spring (B. F. Bush, 1899). 
The leaves shorter acuminate, the longer and thicker costa and chiefly 
the loose areolation, at first sight distingnishes this moss from A. riparium. 
The last character also separates it from A. vacillans Sulliv. From A. 
Kochii Br. Eur. it differs by its larger leaves and its much stronger and 
longer nerve. 
Hypnum malacocladum Card. & Ther. 
Monoicous, fine, soft, rather lax, yellowish-green. Stems filiform, pros- 
trate, denuded/; branches ascending, about 1 cm. long. Leaves quite dis- 
tant, soft, concave, spreading, 0.8-1. 1 mm. long, 0.4-0.5 mm. broad, strongly 
narrowed from an ovate base or oblong, very broadly or shortly acuminate, 
apex rounded or subacute, margins plane, entire, costa thin, simple, extend- 
ing to the middle or beyond, sometimes subfurcate above, 35-40/* thick at 
base ; alar cells rectangular or subhexagonal hyaline, but not forming dis- 
tinct auricles ; median cells shorter rhomboidal, with thicker walls. Per- 
ichaetial leaves erect, longer acuminate, costate; capsule horizontal or 
obliquely erect, short, gibbous, 1-1.5 mm. long, 0.7 mm. thick: opercu- 
lum convex-apiculate, Seta short, rather thick, reddish, 8-10 mm. long. 
Annulus simple, distinct. Peristome 0.4 mm. long, segments of the inner 
peristome narrowly gaping at the keel, slightly papillose above; cilia 1-2. 
Spores 12 ju in diameter. Plate XXV. 
North America: Without locality or name of collector, in herb. L. 
Debat. 
This species somewhat resembles H. Goulardi Sch., from which it differs 
by its longer leaves with a single long costa. It is also distinguished from 
H. Closteri Aust. {Amblystegium Holzingeri Ren. & Card.) by its greater 
size and longer costa. 
The End. 
BOOK REVIEWS. 
Organography of Plants, especially of the Archegoniatae and Spermo- 
phyta, by Dr. K. Goebel, Professor in the University of Munich. 
Authorized English Edition by Isaac Bayley Balfour, Professor of 
Botany in the University of Edinburgh. Published at The Clarendon 
Press, Oxford. 
The first volume of the English translation appeared in 1900. Part II 
was issued last summer. A brief synopsis of the references to the Bryophyta, 
in both volumes, may be of interest and stimulate to further study of the liv- 
ing plants. 
New Formation of Organs in Regeneration: “In mosses the propaga- 
tive capacity is uncommonly great; one may almost say that nearly every 
cell of the vegetative body in mosses and liverworts, and in fact also the 
