Vol. 33 



BULLETIN 



No. 1 



OF THE 



TORREY BOTANICAL CLUB 



JANUARY, 1906 



Hepaticae of Puerto Rico 



VI. CHEILOLEJEUNEA, RECTOLEJEUNEA, CYSTOLEJEUNEA, AND PYCNOLEJEUNEA 



Alexander William Evans . 



(with plates 1-3) 



CHEILOLEJEUNEA 



The genus Cheilolejeunea is not very clearly defined by writers, 

 and some of the species which have been referred to it present but 

 few characters in common. In Spruce's original description of the 

 group as a subgenus, the following are the most important pecu- 

 liarities to which he calls attention : the prostrate stems and 

 branches ; the more or less closely imbricated leaves ; the oblong- 

 falcate lobes, semicordate at the base, usually rounded at the apex, 

 and entire or minutely crenulate on the margins ; the inflated 

 lobules, one fourth to one third as long as the lobes ; the small 

 and often convex leaf-cells, with trigones ; the suborbicular under- 



leaves, one fourth to one half the size of the lobes, bifid to the 

 middle or less with acute segments ; the variability in the length 

 of the female branch ; the usual but not constant absence of a 

 subfloral innovation ; the falcate and spreading bracts, the lobe 

 being commonly broad and rounded and the lobule narrower and 

 acute ; the oval bracteole, shortly bifid at the apex or undivided ; 

 the more or less compressed perianth with theoretically four or 

 five keels, the antical keel being low and often obsolete, the two 

 lateral keels sharp, the two postical keels low and blunt and often 

 confluent into a single broad and rounded keel.* The name of 

 the group refers to the fact that the perianth often becomes two- 



*Hep. Amaz. et And. 251. 1884. 



906.] 



1 



