Mosses and Lichens 



Teeth (peristome}. Cleft to near the base or in the middle 

 only; segments sometimes irregularly torn. 



Annulus. Large, rolling 

 back when mature. 



Spores. Mature in July and 

 August. 



Trematodon longicollis, 

 Michx. 



Trematodon longicollis, the 

 long-necked Trematodon, may be 

 distinguished from Trematodon 

 ambiguum by the neck, which is 

 twice as long as the spore-case, 

 by the shorter plants, and by 

 the slender character of the teeth 

 and the leaves at the base of 

 the pedicel. The specific name 

 longicollis is compounded of two 

 Latin roots, longum, long, and 

 collum, a neck. 



a c d 



T. ambiguum. (a) and (b) old spore- 

 cases; (c) mature spore -case; (d) young 

 spore-case. 



THE LITTLE FORK-MOSSES 

 Genus DICRANELLA, Schimp. 



The species of this genus are generally small with slightly 

 branching stems. The leaves are very long and narrow from a 

 broader often clasping base and are never curled, but spread on 

 all sides or turn in one direction. Usually they are smooth with 

 the margins plane and the vein broad. 



The spore-cases are erect or inclined, symmetrical or un- 

 equal on yellow or red pedicels. They have lids with long 

 awl-like points. 



The peristome consists of sixteen large teeth, two-cleft to 

 about the middle, closely cross-barred and marked with fine 

 parallel bars running lengthwise. 



There are one hundred and twelve species in all, thirty-two 

 known in North America. 



The generic name Dicranella, is the diminutive of Dicranum, 

 from Sttcpavos, a fork. 



150 



