— 40 — 
Key to the Usneas of South America 
— Neuropogon — 
Branches terete 
Apothecial disc ciliate 
Disc black 
Smooth 39. melaxantha 
Verrucose 
Esorediate 42. var. normalis 
Soralio-tuberculate 29. var. granulifera 
Strigose 55. f. strigulosa 
Apothecial disc eciliate 
Disc black 
KHO+ 4. antennarius 
KHO — 18. fasciata 
Subciliate 60. var. sublaevis 
Disc concolorous. 56. var. subciliata 
Branches angulate. 3. var. angulosa 
Uncertain species: 63. U. trachycarpa var. trachycarpoides 
— Excavatae — 
Chondroid axis lacunose, fistulous or 
arachnoid 32. var. implexa 
— Leptinae — • 
Chondroid axis 1-5 diameter of thalloid filament (internodal measurement) 
Erect or subpendulous 
Fibrils spinulous, stipate 
Cortex thin, 50-70/x 
KHO — 17. f. denudata 
KHO+ 58. var. subelegans 
Cortex thick, 170-240^ 
KHO — 34. var. inactiva 
KHO+ 10. cinchonae ( = cinchonarum ) 
Fibrils espinulose, adventive 
Branches angulate, papillate 64. var. trachyclada 
Branches terete 
Cortex simple 
Articulate, KHO-f- 62. var. tincta 
Nonarticulate, KHO — 54. Steineri 
Cortex double 
Fibrils infrequent 
Branches inflated, articulate 
KHO+ 9. var. brasiliensis 
KHO — 33. f. inactiva 
Fibrils frequent, branches 
non-articulate.. . .40. meridionalis 
Uncertain species: 27. U. cornuta var. gracilescens 
