284 SELECTED NOTES. 



may here be follou-ed with great ease. The round grain becomes 

 oval ; then a medial constriction takes place ; the narrow part 

 finally divides, and the one grain becomes two, which remains in 

 contact for a short time. With a high powder the chlorophyll 

 grains appear to be finally punctate, and thus betray a network 

 structure. 



Specimens should be mounted in acetate of potash, but obser- 

 vation is best conducted on a fresh material. With careful exami- 

 nation of the Pyrenoids the starch enclosures may be seen ; but 

 as chemical re-agents are required to show them to their best 

 advantage, I refer our readers to Hillhouse's edition of Strasburger 

 as containing all the information they desire. 



Moss is not a plant of very great use to man. The Laps use it 

 to stuff mattresses, etc., and in the Midlands it is used in wells, 

 when running sand gives trouble, but its uses are very limited. It 

 occupies an important ])lace in the evolution of plants, and is of 

 considerable interest from a paleo-botanical point of view. The 

 sphagnums, which are hardly true mosses, are a large ingredient 

 in peat, and in a more recent state form the Peat-Moss Litter, so 

 extensively used for stables. It will be seen that the Andreceacece 

 form a sort of connecting link between the true mosses and 

 Jungermanacece. 



EXPLANATION OF PLATE XV. 



Fig. 1.— rt, Capsule of Atrichum midulatum, divided longitudinally; 

 h, ditto, showing Columella ; c, Calyptra ; d and e, Peristoma 

 and Epiphragm ; /, Mature capsule without calyptra, which 

 IS shown at c ; g and j, Mature capsules without calyptra and 

 operculum ; h and i, Operculum. 



,, 2.— Shows the mature capsule, a. Spore case; h, Calyptra; 

 c. Operculum ; d, Annulus ; e, Seta. 



,, 3.— The same fruit after removal of the calyptra and operculum, 

 thus disclosing the peristome previously concealed. a, Peri- 

 stoma ; 6, Seta ; c, Spore-case ; cZ, Calyptra ; e, Operculum. 



„ 4.— Peristome of Georgia pellucida. 



„ 5.— Dry Capsule of Andnea petrophila. 



,, 6.— Capsule and perichretral leaf of Archidium alternifolinm. a, 

 Calyptra. 



„ 7. —Capsule of Pottia Heimii, showing absence of peristome. 



