POLYTRICHACE.E.] 37 [Catharinea. 



interspaces. In the young state, these mamillae reach down to the basal 

 membrane, but in the mature fruit contract by drying, and the spore sac also 

 rupturing, through these apertures, as in the fruit of Papaver and Campanula, 

 the spores escape. The remaining species form the subgenus Leiodon and in 

 this as well as in Catharinea and Oligotrichum the wing-like crest is wanting, the 

 epiphragm is thick, concave, and generally somewhat hollowed in the centre, 

 the margin toothed with thin processes curved upward and inward, and 

 closely fixed to the upper part of the teeth, which they resemble in structure. 

 For this reason the epiphragm is not strictly contained within the apices of 

 the peristome, but hangs down from them for the length of the dentiform 

 processes, connate with the highest part of peristome. Mamillae are also 

 absent from the under surface, and the spores are much larger." 



The leaves of Polytrichaceae, except in Catharinea and Racelopus, are 

 thick and opake, from the presence on the upper surface of numerous longi- 

 tudinal lamellae, and the number and structure of these lamellae, as seen in 

 transverse section, are as Prof. Lindberg points out, of the greatest import- 

 ance for a proper discrimination of the species, especially in the barren state ; 

 the cells forming their free margin are particularly to be noted, as they vary 

 considerably in different species. 



In Catharinea the lamellae are few and confined to the nerve, and are 

 chlorophyllose like the leaf lamina, but in Polytrichum the lamellae alone 

 have chlorophyllose cells. 



Pogonatum is not separable from Polytrichum as a natural genus, for 

 in a large proportion of species referred to Pogonatum (forming the section 

 Anasmogonium MITT.), the capsule is 6 8 plicate, while in some Polytricha 

 the angles of the capsule are almost obsolete. 



It may be noted that Pol. commune is one of the few mosses which have 

 been put to economic purposes. Linnaeus tells us that the Laplanders use 

 it for beds, and commends it as not harbouring fleas or any infectious disease ; 

 in the north of England it is also made into small dusting brooms and mats. 



i. CATHARINEA EHRHART. 



(Hannov. Mag. 1780, 59 Stuck, p. 933 ; et Beitr. i., pp. 126 et 178 (1787). 



Plants mnioid, gregarious or ccespitose, throwing up erect stems 

 from a creeping, subterranean rhizome. Leaves Ungulate or oblong, 

 generally undulated, crisped when dry ; bordered and serrate at margin ; 

 the nerve with few lamella? ; areolation chlorophyllose, rounded 

 hexagonal. Calyptra narrow, cucullate, spinulose only at apex. 

 Capsule oval or cylindric, subarcuate ; annulus none ; lid convex, long- 

 beaked ; teeth of peristome 32, lingulate, rigid, with a narrow basal 

 membrane ; sporangium close to the wall of capsule ; spores minute, 

 smooth. Inflorescence usually dioicous ; the male cup-like, with 

 numerous bracts and filiform paraphyses. 



This genus was founded by Ehrhart in honour of Catharine II. Empress 

 of Russia, and for the reasons stated under Georgia, yet Schimper displaces it 



