436 A. W. Evans — Uaicaiian Hepatuae of the Trlhe Juhuloidece. 



The four genera Ilygrolejeunea, JRuosmolejeunea, Cheilolejeunea 

 and Pycnolejeunea are so closely allied that they might consistently 

 be placed in a single genus. It is not only difficult to define them in 

 a satisfactory way, but there are sevei^al species which fit in one 

 about as well as in an(i)ther. In fact, writers are apparently most 

 uncertain as to the limits of these groups, and we find that certain 

 species are placed in different genera by different authors or even by 

 the same author at different times. A few illustrations of this state- 

 ment may be quoted : 



Lejexmea duriuscula Nees is placed b}^ Spruce in Cheilo-Lejeunea ;* 

 a few years afterwards Stephani, in his valuable revision of the 

 genus Lejeunea,\ places it in Etiosmo-Lejeunea, and, on the very 

 next page of the same article, puts it back into Cheilo-Lejeunea; in 

 Spruce's last paperj he too places it in Euos'ino-Lejeunea. 



Lejeunea adnata Kunze is placed by Spruce in Cheilo-Lejeunea (as 

 L. confluens Lindenb., a synonym)§, while Stephani places it in 

 Fycno-Lejeunea. \ 



Lejexmea jyhyUohola Mont, is placed by Spruce in Cheilo-Lejeunea^ 

 and by Stephani in Sygro-Lejeunea.** 



Of the four species here referred to Cheilolejeunea, all have been 

 found with perianths except C. Sandvicensis. They are very uni- 

 form in appearance, and, with the exception of C. ste?ioschiza, are 

 all of about .the same size. This species is considerably larger than 

 the others, and apparently on account of its robustness, is placed by 

 Herr Stephani in Pycnolejeunea, with which it certainly has much 

 in common. 



1. Cheilolejeunea stenoschiza (Angstr.). 



Lejeunea stenoschiza Angstr. Ofversigt af Kongl. Vetensk. Akad. 



Forhand. xxix, Haft 4, 26. 1872. 

 Pycnolejeunea stenoschiza Steph. Bull, de I'Herb, Boissier, v, 842. 



1897. 



Plate LIIL, figs. 1-7. 



Autoicous: plants brownish-green, closely appressed to substratum 

 and sometimes forming patches of considerable extent : stems irreg- 



* Hep. Amaz. at And. 259. 1884. || Hedwigia, xxix, 81. 1890. 



t Hedwigia, xxix, 80, 81. 1890. T[ L. c. 259. 



X Jour. Linn. Soc. Bot. xxx, 346. 1894. --^* L. c. 81. 

 § Hep. Amaz. et And. 252. 1884. 



