CRYPTOGAMIA ALG^E. 793 



FEM. Calyx leflilis, campanulatus, polyfperinus. 



jf>o/ymGrpha MARCHANTIA calyce communi decemfido. 

 -' Sj). pi. 1603. (Michel, ^en. t. \. f. 1. I)illen,mi<Jc. 



t. 76./. 6.) 



Great ftar-headed Marchantia, Angus. 



On fhady moift rocks, on the banks of rivulets, 

 and the fides of wells, and fometimes in bogs. 

 V-VII. 



The leaves are about three inches long, from 

 half an inch to an inch wide, lying fiat upon 

 the ground, and adhering clofely to ir by nu- 

 rnerous downy radicles, which grow out of the 

 middle and bafe of the leaf, on the under fide. 

 Thefc leaves are varioufly divided into obtufe 

 lobes, finuated on the edges •, their upper fur- 

 faqe of a dark, fliinmg, green colour, reticu- 

 lated with numerous minute rhomboidal, or lo- 

 ?cnge-like fcales, and divided in the middle by 

 a black purple vein ; their under fide is of a 

 paler green, and then- fubllancc coriaceous and 

 nearly opake-."' y, ':•. ■ -"> 



The fruftihcatjons are of three kinds. The Jjrjl: 

 are fiat, circular umbels, a quartt-r of an inch 

 in diameter, arifing generally out of the finules 

 of the leaves, at firft feflile, but afterwards 

 elevated on firm pedicles, from half an inch to 

 an inch high ; at firft whitifli, but afterwards 

 turning to a dark brown or black ifii colour. 

 Thefe umbels are at firft entire on the ed^es 

 but afterwards divided into feven, ei"ht,^or 



nine. 



