March 1, 1892.] 



KNOWLEDGE. 



41 



^^ AN ILLUSTRATED "^^ 



MAGAZINE OF SCIENCE 



SIMPLY WORDED— EXACTLY DESCRIBED 



LONDON: MARCH 1, 1S92. 



CONTENTS. 



PAGE 



British Mosses. By the Kt. Hon. Loed Justice Fet, 



F.K.S., F.S.A., F.L.S. 41 



The Life of an Ant. — I. By E. A. Butlbb 43 



Elephants, Recent and Extinct. By R. Ltdekkek, B.A. 



C'aiitab ... ... ... ... ... ... ... 46 



The Movements of the Stars By Miss A. M. Cleeke 48 



The Moon s Atmosphere. By A. C. Rantaed 50 



Letters :— W. H. S. Monce ; C. E. Peek ; Wm. Noble ; 



C. E. Peek; W. H. S. MoNCK; B. Noble 51 



Camphire and Camphor. By J. Ch. Sawee, F.L.S. ... 55 



The Face of the Sky for March. By Heebeet Sadlbb, 



F.R.A.S. 57 



Chess Column. By C. D. Locock, B.A.Oxon 58 



BRITISH MOSSES. 



By the Rt. Hon. Lord -Justice Fry, F.R.S., F.S.A., F.L.S. 

 (Continuiil from payc 25.) 



IF the reader will, now return to my table A, at the 

 beginning of this article, he will see that I have 

 given some accoimt of all the i\lusci except the 

 Anomalea' ; these are a somewhat heterogeneous 

 group of plants, of great interest to the botanist, 

 but with which I fear to detain my reader lest I should 

 disgust him with apparently dry details. 



Siihiiiiixtccce. — Next in order to the Musci in my table A 

 will be found the Sphagnacese, or Turf or Peat Mosses, 

 a natural group of comparatively few species and very 

 marked organization. The general appearance of this 

 class of Mosses may be gathered from the figure of one 

 already given (see Fig. 16), and is well known to almost 

 everyone who has had any interest in a hot-house. 



Vast tracts of land in this country and throughout 

 Northern Europe and America are covered with plants of 

 this group, and large tracts which are now fertile agricul- 

 tural land, where they have entirely ceased to grow, have 

 in former times been occupied by them. The bogs of 

 Ireland, which are mainly constituted of Turf Moss, were 

 computed in 1819 by the Bog Commissioners to occupy 

 2,830,000 acres. No Moss has probably ever, at least in 

 the present state of the globe, played so large a part as the 

 Sphagnum or Turf Moss. 



Strurtiirr. — It is to the peculiar structure of the Peat 

 Moss that this great part on the theatre of the globe is to 

 be attributed. 



Lcdirs. — In the young leaves the component cells are all 

 alike ; then by a differential growth we are presented with 

 large cells (sometimes of a square or rectangular shape) 

 surrounded by narrower cells ; then chlorophyll forms in 

 these narrow cells, but is absent from the square cells; 

 from these the contents disappear, and water or water -like 

 fluid occupies the whole cell ; subsequently annular and 

 spiral threads develop on the walls of the square cells. 

 The intimate structure of the leaf thus enables it to absorb 

 great quantities of water. 



But again, the shape of the leaves is in many species 

 adapted to the retention of water. By a retardation of the 

 lateral as compared with the mesial growth, the leaf 

 assumes a boat shape. Often the edges of the leaves are 

 turned over ; the leaf thus affords means of holding water. 



Figs. 27 and 28 will enable the reader to follow 



... p 





'rlA 



^ffV^ - * Fig. 28.— Portion of leaf of .S>^aj»t«w. 

 acutifolium, highly ni.agnified ; o n. 



Fig. 27. — Leaf of Sphnij- orifices opening from interior uf cells. 



num acittifolium, magiii- After Schimi)er. 

 fietl ; s s, stem ; p, point 

 of the leaf. After Schim- 

 per. 



the foregoing description. Fig. 27 shows a magnified 

 leaf of the Sphdiinum acuti folium — with a portion of the 

 adjoining stem (.v.s), of which more hereafter. The edges 

 of the leaf are turned over — as may be seen by looking at 

 the extreme point of the leaf ( /i) where these foldings over 

 cease. Fig. 28 exhibits a portion of a leaf far more highly 

 magnified ; the large cells free from chlorophyll bounded 

 by the narrower cells charged with it will be at once 

 observed as well as the spiral threads developed on the 

 walls of the larger cells, a peculiarity of the leaf of this 

 genus which enables one to detect the presence of its 

 remains so long as any organic structure is retained ; and 

 at the points o o are seen orifices opening from the 

 interior of the cell and admitting water. 



A reference to Fig. 10 will show that the leaves of the 

 Sphagnum are borne on lateral branches. These at the 



