A. W. Evans — Havmiian Hepaticce of the Tribe Jiibuloidece. 447 



I. Subgenus Physocolea (Spruce) Schiffn. 



1. Cololejeunea Cookei sp. nov. 

 Plate LVI., figs. 6-14. 



Autoicous : plants green or brownish-green, growing in loose thin 

 mats : stems irregularly branched : leaves distant, the lobe broadly 

 ovate, squarrose, attached to the axis by a very narrow base, rounded or 

 very obtuse at the apex, crenulate from projecting cells; lobule ovate, 

 jDlane or somewhat inflated, keels strongly arched, crenulate, free mar- 

 gin plane throughout or slightly involute at base, ending in a blunt 

 tooth and bearing between this and the end of the keel a second tooth 

 composed of two cells, crenulation less marked than on the lobe ; stylus 

 a single cell, often obsolete: leaf -cells papillose, thin-walled and with- 

 out trigones : ? inflorescence borne on a principal branch, innovating 

 on one side, the innovation inserted at or above the level of the oppo- 

 site bi'act, long, not immediately floriferous ; bracts at different 

 levels, slightly bifid, the lobe and lobule rounded or very obtuse at 

 the apex, crenulate ; perianth obovate from a narrow, often stalk-like 

 base, rounded above and narrowed into a short beak, sharply five- 

 keeled (one antical, two lateral and two postical), the keels slightl}^ 

 crenulate : $, inflorescence terminal on a principal branch, large for 

 the size of the plant ; bracts in ten or more pairs, closely imbricated, 

 subequally bifid ; antheridia two in each axil : spores more or less 

 oblong in shape, greenish, with a rather thick, yellowish, minutely 

 tuberculate wall. 



Stem O-OS™"" in diameter, leaf -lobes 0.25x0.2°^'", leaf-lobules, 

 0.18 X 0.1™"^, cells at edge and in the middle of lobe 16/li in diameter, 

 at the base 18/x, lobe of bract 0.4x0.15'^", lobule 0.35x0.1'"'", 

 perianth 0.6 x 0.35'"'", spores 25/* in shortest diameter. 



On bark of trees. Kauai : Molokoa, Kipu (Cooke). 

 Cololejeunea Cookei may be at once distinguished from all the 

 other Hawaiian species by its minute size, its more or less squarrose 

 leaves, its proportionately large lobule, which is often three fourths 

 as long as the lobe, its crenulate leaf-margins and its sharply five- 

 keeled perianth. A much nearer relative is the well-known C. rainu- 

 tissima (Sm.) Schiffn. of Europe and the southern United States. 

 This species is, however, a little larger and has larger leaf -cells ; 

 its perichsetial bracts are subopposite and the innovation is usually 

 below the opposite bract ; the male spike is smaller and is situated 

 on a small lateral branch. According to Spruce*, the 3 bracts of C. 



* Hep. Amaz. et And. 293. 1884. 



