ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
313 
; well bring out some close relations between parasitism and the epi- 
pkyllous habit. Parasitism is possibly an advanced, specialized phase 
of epipkytism. A. G. 
Researches on the Development of the Leaf of Mosses. — J acques 
Pottier (Ann. Sci. Nat. Bot ., X e Ser., tom. III., 1921, 1-144, 368 figs., 
2 pis.). An elaborate study of the leaf-development of some types of 
| mosses ( Andresea , Mnium , Atrichum, Dicranum, Barbula, Funaria, 
Leucobryum) by means of serial transverse sections, very careful drawings, 
i! detailed descriptions, and leaf reconstruction by means of plasticine or 
modelling wax. The principal results are claimed to be as follows : 
|; (1) The leaf of mosses grows by means of an initial cell only at the 
very beginning of its development. (2) The growing region is trans- 
[ f erred from the apex to the base of the leaf. (3) The leaf apex is 
g! differentiated very early. (4) Some species of Andresea with costate 
I leaves, such as A. crassinervia and A. angustata, sometimes have in 
j[ their leaf an initial cell with two faces. This, added to the observations 
I of Kuhn and Berggren, shows that in this archaic genus there is a clear 
I tendency towards the mode of growth found in the higher mosses, 
t (5) The embryogenesis of Mnium punctatum proves that the leaf 
margins are in no way comparable with the nerves. (6) A comparative 
| study of the development of the group of stenocyst cells in various 
- mosses shows that their origin is not always the same. (7) There 
t certainly is a foliar asymmetry in the leaves of Leucobryum glaucum , 
)' although Lorch denied it, and this is a fresh argument for its generality 
! in the mosses. 
A review of the work by W. H. Emig has been published in 
Bryologist , 1921, 24, 78-80, in which some criticisms are offered and 
I certain important omissions from the bibliography and historical 
{ summary are made good. A. G. 
Some New Genera of Mosses. — H. NT. Dixon (Journ. of Bot., 
1922, 60, 101-110, 1 pi.). Descriptions and figures of seven new 
I genera and six species. Nanobryum (type, N. Dummeri), from East 
-t: and South Africa, shows a vegetative affinity with Dicranellaceae, but in 
i sporopkyte characters resembles Fissidens. Ghionoloma (G. induratum ), 
j from Birmah, characterized by the white border and the structure of its 
1 tough leaves, belongs to the Trichostomeae, but is sterile. Beddomiella 
(B. funarioides), from the Nilghiri Hills, is Pottiaceous. Oedipodiella 
V (0. australis ), from S. Africa, is allied to Oedipodium. Chamsebryum 
\ ( G . pottioides ), from S. Africa, belongs to Funariacege, and is allied to 
v Gostesia Tker., a recent Chilian addition. Physcomitrellopsis (F. africana ), 
o from Natal, is allied to Physcomitrella : (a key to the sixteen genera of 
Funariaceae is supplied). Dimorphocladon (D. bornense), from Borneo,. 
: is allied to Ghsetomitrium , Hookeriaceae. A. G. 
West Indian Mosses. — R. S. Williams (. Bryologist , 1921, 24, 
65-67, 1 pi.). A list of eleven mosses collected at the Kaieteur 
Falls in British Guiana, and eighteen on the island of Dominica, by 
Miss E. F. Noel in 1914. New to science is Macromitrium trinitense,. 
|| which is described and figured ; it is distinguished by its long slender- 
