A. W.' Evans — Hawaiian Hepaiicoe of the Trihe Juhuloidem. 423 



7. THYSANANTHUS Lindenb. 

 Thysananthus Lindenb.; G. L. & N. Syn, Hep. 286. 1845. 

 Lejeunea subgenus Thysano-Lejewiea Spruce, Hep. Amaz. et And. 



105. 1884. 

 Lejeunea subgenus Dendro-Lejeunea Sj^ruce, 1. c. 110. 

 Lejeunea subgenus Phrag mo -Lejeunea Schiffn. & Gottsche, Leber- 

 moose der Forschungsreise S. M. S. "Gazelle," 24. 1890. 



Plants large, green or brownish-green, usually in depressed tufts : 

 stems growing from a more or less distinct creeping caudex, pin- 

 nately or dicliotomously branched, sometimes with slender flagelli- 

 form branchlets : leaves imbricated, the lobe ovate to ligulate, usually 

 more or less recurved on postical margin, entire or usually somewhat 

 dentate near apex, lobule small, more or less inflated, with one or two 

 minute teeth on free margin near apex : underleaves ovate to orbic- 

 ular, narrowed toward base, truncate to broadly emarginate at the 

 entire or denticulate apex : leaf-cells with distinct trigones, more or 

 less elongated in the middle and toward the base of lobe : ? inflor- 

 rescence borne on a stem or principal branch, innovating on one or 

 on both sides, the innovations usually floriferous ; bracts unequally 

 bifid, the lobe narrower than in the leaves, entire or toothed, lobule 

 small; bracteole truncate or shortly bifid, mostly dentate ; perianth 

 linear to obovate, trigonous but sometimes with supplementary keels, 

 the keels usually dentate- or laciniate-winged : 5 inflorescence ter- 

 minal or intercalary on a principal branch. 



1. Thysananthus elongatus (Aiist.). 



Phragmicoma elongata Aust. Proc. Acad. Nat. Sci. Phil, for 1869 : 



225. 

 Lejeunea aliena xlngstr. Ofversigt af Kongl. Vetensk. Akad. For- 



handl. xxix, Haft 4, 23. 1872 (misprinted "Z. alcina''''). 

 Lejeunea elongata Aust. Bull. Torr. Bot. Club, v, 17. 1874. 

 Licranolejeunea Lidericiana Steph. Hedwigia, xxxv, 77. 1896. 

 Brachlolejeunea aliena Steph. Bull, de I'Herb. Boissier, v, 842. 1897. 

 Ptycholejeunea elongata Steph. 1. c. 



Plate XLIX. 



Autoicous or dioicous: plants brownish-green, sometimes bright 

 or yellowish-green, very variable, in some cases closely appressed to 

 substratum but usually growing in wide depressed mats : stems 

 irregularly pinnate, or, on fruiting plants, usuall}^ diochotomous : 

 leaves imbricated, sometimes densely so, not squarrose, the lobe 



