Pleuroclada 79 



cylindraceo-oblonga; valvulse lineari-lanceolatse ovalesve, idem ao ela- 

 teres sporaeque purpureo-badies ; cellulis bistratis, interioribus fibra an- 

 nular! — saepe ex. p. dissoluta et ad trabeculas redacta — impletis con- 

 flatae. Pedicellus sat crassus, cellulis magnis, demum 4 — 5 plo longi- 

 oribus quam latis, prismatico-cylindricis, corticis 8 — 9-seriatis primum 

 chlorophyllo repletis posterius evacuatis, internis asquimagnis 4 — 5- 

 seriatis ab initio subvacuis. conflatus. Elateres capsula 4 plo breviores 

 filiformes utrinque obtusi', fibra spirali duplici angusta impleti. Spora 

 latitudine elaterum globossB Iseves. Andrcecia . . . . — Folia '5 x "5 

 •65 X -65, -55 X -65; c i/3°; f i^-e x 3, -5 x -38, -55 x -4— '45; bract, ext. 

 •75 x "7, int. 1.3 x -9; per 4-0 x *7 — •%5;p>edic 10.0 — 15-0; caps -8 x "5; 

 elat. -2 — -25 i"*". 



Var. scotica, foliis paulo latioribus quam longis concavissimis, ad ^ 

 alt. solum bilobis ; foliolis latis, ovatis, hinc vel ssepius utrinque uni- 

 dentatis, superioribus saepe bifidulis. Jung albescens Hook, (typus). 



Var islandica, foliis exacte fere orbiculatis, minus concavis, baud rare 

 ad \ usque fissis ; foliolis ovato-lanceolatis integerrimis. — Jnng. islandica 

 Nees Hep. Eur. II, 29 ; Syn. Hep. 182. 



• Hah. var. scotica, in montibus Scoticis (Clova ! Greville) ; in alpibus 

 Helveticis [Grimsel ! Schimper : specimina ditissime fertilia); in alpibus 

 Tyrolensibus ! (jAck in G-. et E. &c. 85 et 468.) 



Var. islandica, in Groenlandia ! (Vahl) ; in rivuli ripa Lapponisa 

 Umensis! Angstr.in G et Eab. Hep. Eur. 886.) — Exempla Schimperiana, 

 quoad folia valde concava perpaulo ultra i fissa, inter has duas formaa 

 intermedia sunt. Perianthia paulo minus crassa quam in stirpe 

 Grcenlandica. 



Obs. In G. et Rab. Hep. Eur. exsicc, under no. 386, {jfung. islandica) Dr. 

 Gottsche has the following remark. "Richard Spruce has proposed, in his ' Musci 

 and Hepaticse of the Pyrenees', in the 3rd volume of Trans. Bot. Soc. Edinb. (1849) 

 his herbarium name Trigonanthus for the yungermanice bicuspides ; but all the plants 

 enumerated under it he still distinguishes by the old name, yungermania. Our 

 specimens were sent by Angstrom as Trigonanthus islandicus, in accordance with 

 the proposed nomenclature of R. Spruce". This is an instance of a conclusion 

 drawn from insufficient premises ; for, even in my first attempt to separate Trigon- 

 anthtis from yungermania, I was careful to exclude y. albescens (i.e. islandica) from 

 the list of typical species. I noted, even then, an approach of y. albescens to Lepidozia 

 reptans, in the bluish-white tinge of the dried specimens, the pinnate branching, with 

 a difform leaf subtending each branch, and the concave leaves with connivent lobes. 



