245 

 KEY TO THE HARPIDIOID HYPNA. 



J. A. WHELDON. 



{Co?itinued froin page 20). 



(A) ScoRPiDiUM (Schimp.) Limpr. 

 Leaves broad, concave, turgidly imbricate, more or less obtuse, 

 apicu late -acuminate, or apiculate, often somewhat rugose when dry. 

 Nerveless, or with a short forked nerve. Cells long, narrow, incrassate 

 and porose. Auricles none, or of a few cells, not very distinct. Seta 

 long. Annulus triple (where known). Dioicous. 



1. Leaves homomallous, falcate -secund above forming a hooked 

 cusp at stem apex (2). Leaves imbricate appressed : stems and branches 

 turgidly julaceous, ending in a straight, or nearly straight, cusp (5). 



2. Leaves broadly oval, blunt and apiculate or shortly cuspidate- 

 subulate (3). Leaves narrower, oblong lanceolate, shortly acuminate- 

 subulate, more distant, often regularly falcate -secund throughout 

 (S. scorpioides var. angustifolium) . 



3. Stems elongate, slender, subsimple or pinnate, upper half of the 

 leaf recurved (5. scorpioides var. gracilescens) . Shorter, stout to very 

 robust, irregularly, fastigiately branched, or imperfectly pinnate : 

 leaves densely intricate, their points recurved (4). 



4. Bright green above, brownish below (S. scorpioides var. typiciim 

 f. virescens). Yellowish above, soon fuscescent or nigro-fuscous below 



(S. scorpioides var. typicum f. fuscescens). Blotched with rich purple 

 red (S. scorpioides var. typiciim f. versicolor) . 



5. Cells narrowly linear, about fifteen times as long as wide, almost 

 uniform to base (6). Cells shorter and wider, upper elliptical linear 

 five to eight times as long as wide, gradually becoming longer and linear 

 rectangular below : alar cells rather numerous, wide, rectangular, forming 

 indistinct, not inflated auricles (5. turgescens) . 



6. Plants rather short and slender, irregularly branched green or 

 yellowish -green, passing to fuscous-yellow (S. scorpioides var. julaceum 

 f. flavovirens) . Subsimple, with a few ascending weak branches : leaves 

 very obtuse, oval, purpurescent (S. scorpioides var. julaceum f. 

 rubrotinctum) . Robust, tall, simple or slightly branched : tips of stems 

 fuscous-yellow, below brown to black (S. scorpioides var. julaceum f. 

 fuligineum ) . 



(B) LiMPRiCHTiA Loeske. 



{Harpidia intermedia Sanio. Intermedius-Gruppe Warnst. 



Vernicosus-Gruppe Roth.) 



Leaves usually strongly falcate to circinate, uniform, entire, smooth 

 or plicate. Nerved to middle, or beyond, but never excurrent. Lamina 

 cells narrow, vermicular, thick walled and often porose, auricles absent. 

 Inner perichaetial leaves sulcate. Annulus wide. Monoicous or dioicous. 



1. Stem without central strand or differentiated epidermis : leaves 

 rather shortly and widely acuminate, more or less distinctly plicate, 

 nerved beyond middle (2). Stem with central strand and enlarged 

 epidermal cells (4). Stem with central strand but without differentiated 

 epidermis, 3-5 cm. high : leaves small, falcate, ovate lanceolate, acumen 

 short and broad, nerve very strong (L. latinerve). 



2. Stems erect, rigid, tufts yellow-green to rufous brown (5-10 cm. 

 high) : leaves plicate, concave, with a rapidly contracted short recurved 

 canaliculate point : basal cells in several rows wider, hexagono-oblong, 



1921 July I 



