The Genus Cephalozia in North America. 



By Lucien M. Underwood. 



The Trigonantheae as outlined by Richard Spruce form a 

 somewhat natural group of the Jungermaniaceae. With us the 

 species are all foliose, but in certain neo-tropical genera the 

 gametophyte is reduced almost to the condition of protonema, 

 producing leaves only on the branches bearing the sex apparatus. 

 In the Australasian genus Zoopsis , the simple thalloid shoot in some 

 species is provided with rudimentary leaves only, formed of one or 

 two cells. The tribe, therefore, contains within itself, some of the 

 connecting links which ally the more usual forms to the simple 

 primitive hepatics. 



The tribe is characterized by the archegonia being borne on a 

 usually short ventral branch,* with a normally triangular perianth, 

 so placed that the third or odd angle is ventral, the remaining two 

 being lateral. The underleaves are usually wanting or small, only 

 attaining the dignity of a third series of leaves in some of the 

 species o{ Lepidozia, though in Bazzania and Kantia they are well 

 marked structures. The tribe contains some species that form con- ' 

 spicuous mats like Bazzania, but others are small, minute or even 

 microscopic in size. They inhabit old logs, or grow on the ground 

 in swamps, on clay banks or occasionally even in sand and on the 

 faces of moss-covered rocks, but with us are rarely, if ever, found 

 on erect trees, where the species of Friillania, Lejcunea, Radiila 



* Exceptions to this occur in some rare species of Cephalozia where they are 

 terminal. 



