WEST INDIAN IlEPATICiE 227 



on the face of it tlie immensity of the task undertaken by Stephani 

 in describing the llcpaticw of the world precludes the possibility of 

 doing full justice to all the species, although admiration is none the 

 less due to him for the great work he has done. 



Hub. Jack-in-the-13ox Gully, Barbados, March 1S9C. 



P. AKGUTA Gottsche. 



So named by Stephani, I cannot find any mention of this species 

 in Sp. Hep. or elsewhere. Stephani lists a P. arcjuta Steph. in his 

 Sp. Hep. from Patagonia. 



Hab. Mountain Lake, Dominica, Jan. 1890. 



P. TENUIS Lindenb. Sp. Hep. p. 50. 



Ilab. Mountain Lake, Dominica, Jan. 189G. 



P. HusNOTi St. Sp. Hep. p. 50G. 



Ilab. Mountain Lake, Dominica, Jan. 1S9G. 



Metzgeria Armilagei, n. sp. 



Dioicous; pale green, delicate, flaccid, stratose ; medium size; 

 stem repeatedly dichotomous, patent (50°), linear, margins recurved; 

 costa firm ; cortical cells small, similar to inner, 10 to 12, 4 to 5 

 antical, G postical, inner cells opaque and indistinct, cross-section 

 oval-oblong, postical side setose ; wings 18 to 20 cells wide, glabrous ; 

 adjacent cells to costa large, cuticle minutely papillose ; cells medium 

 to rather large, quadrate or oblong-quadrate, 4 or 5 sided ; walls thick, 

 no trigones, marginal cells similar, slightly ci-enulate ; margin setose, 

 setaj short, single or in pairs, straight or slightly hamate. JSTon- 

 gemmiparous. 



Dimensions. Stems 1 to 1^ inches long, '2 mm. wide, cells "04 

 mm. X -04 mm., -04 mm. x Od mm., setae '075 mm. long. 



Ilab. Near Maracaas Falls, Ti-inidad, April 1896: Dominica, 

 Jan. 189G. 



Obs. As the structure of the Metzgericd is so simple and rudi- 

 mentary, only a few characters can be depended upon in the description 

 of species; amongst them is the structure of the costa or midi-ib, 

 which is found to be very constant in all species. M. Armitagei has 

 a costa with a cortical layer of 10 to 12 small cells; the only other 

 species with this character is M. dichofoma (Sw.) from the West 

 Indies and Brazil. The short diagnosis in Syn. Hep. (1844) is of 

 little help. Lindberg describes and figures it in his monograph on 

 MetzgerifB (Acta Soc. p. P. et P. fenn.l. p. 20 (1877)) with postical 

 side of leaves setose-pilose, pili long, leaf cells '035 mm. x '05 mm. 

 Stephani says (Sp. Hep. p. 943) cells '027 mm. x -030 mm. The 

 specimens from Brazil, Caldas, 1854, G. A. Lindberg (M. Mus. 

 n. K. 3G40), which I have had the opportunity of examining, agree 

 with Lindberg's description ; but I find the cells measure less than 

 either Lindberg or Stephani states, namely, only -02 mm. x "025 mm., 

 •025 mm. and "02 mm. X '03 mm. 



There are specimens in the Manchester Museum named Metzqeria 

 dichotoma (Jamaica, Dickson, Herb. Tayl. & Wilson, 1870, Herb. 

 James) which bear no relation to M. diclioto7na, having a costa with 

 two large antical and two large postical cortical cells ; the wings are 

 glabrous, but the costa and margin are furnished with long hamate 



