MUSCI ACROCARPI. 



Fruit terminating the axis of stem, or becoming apparently lateral 

 through being pushed aside by a new shoot. 



Sect. i. SCHISTOCARPL 

 Capsule splitting vertically into valves united at base and apex. 



Fam. i. ANDRE^ACE^E. 



Mosses with the habit of the genus Grimmia, always growing on 

 quartzose rocks, attached by a few radicles, and forming small, dense, 

 very fragile, fuscous, rufous or black tufts. Stems rigid, slender, 

 dichotomous or fasciculate. Leaves in 5 or 8 ranks, patent, secund 

 or falcato-secund ; smooth or papillose, nerved or nerveless, ovate, 

 lanceolate or subulate ; the cells minute, incrassate, rectangular at 

 base, punctiform or angular above. 



Fruit terminal, solitary, enclosed in the large perichaetium up to 

 maturity, then exserted on the elongated vaginula. Capsule ovate- 

 oblong, without operculum, splitting into 4, or rarely 6 8 valves, 

 united at apex, closed when moist, gaping widely and depressed when 

 dry ; the wall of five cell-strata, without a distinct sporangial membrane ; 

 columella cylindric, extending from base to apex. Calyptra campanu- 

 late, closely adhering to capsule, mitriform, torn irregularly. Spores 

 smooth. Male inflorescence gemmiform, terminal, or lateral by arrest 

 of development. 



The species of Andnaa were united by the early authors with Jungev- 

 mannia, but they agree with the true mosses in all points of structure, the 

 only aberrant character being the valvate dehiscence of the capsule, giving 

 them a superficial resemblance to that genus of Hepatica, to which also they 

 slightly approximate in the form of their prothallium. Their true place 

 appears to be between the Sphagnacea and frondose mosses, since they 

 present certain points of agreement with the former, in the capsule being at 

 first enclosed in a similar large saccate calyptra, and then elevated on an 

 elongated pseudopodium, and also in the prothallium partaking somewhat of 

 the lobate form seen in Sphagnum. 



The plants entirely agree with the genus Grimmia in habit, mode of 

 growth, and structure of leaves, but they deviate so widely from it in the 

 fruit, that I prefer to follow Bridel in retaining them in a separate section. 

 My friend Lindberg places them as the lowest family of the acrocarpous 

 mosses, and next after the Grimmiacete. 



