276 PROCEEDINGS OF THE AMERICAN ACADEMY 



areolata excepta, lamina dorsali ad basin sensim evanescente, margi- 

 nibus omnibus limbo angusto integro e cellulis linearibus constructo 

 circumcinctis, costa cum apice evanida ; capsula terminali ovali-oblonga, 

 pedicello apice incrassato ; operculo longirostrato ; calyptra dimidiata. 

 — Wet banks of rivulets. — A very small species, remarkable for the 

 apophysate appearance of its capsule, owing to a thickening of the 

 upper part of the pedicel. Stems 2-3 lines high, with bright-green 

 foliage, crisped when dry. 



21. F. PETROPHiLUS (sp. nov.) : monoicus rigidus gracilis, basi 

 nudiuscula fasciculatus, prolifero-elongatus ; foliis circiter 30-jugis con- 

 fertissimis erectis longissimis angustis e basi ad apicem sensim acumi- 

 natis, duplicatura inaequali f et ultra producta, lamina dorsali angusta 

 supra basin sensim evanescente, cellulis firmis pellucidis flavidis sub- 

 rotundis illis secus costam sub apice evanidam majoribus ; capsula 

 terminali inasquali-oblonga subinclinata brevipedicellata ; operculo et 

 calyptra precedentis. — On rocks in ravines. — Fronds 8 — 10 lines 

 high, slender, gradually increasing in width towards the top, where 

 they are nearly one line wide. Foliage of a firm texture, dark green 

 dashed with light brown, not crisped when dry. 



Gen. TREMATODON, Eich. 



22. T. LONGicoLLis, Rich.; Schivcegr. Suppl. t. 126. — On banks, 

 rare. 



Gen. TRICHOSTOMUM, Hedw. 



23. T. CAXALicuLATUM, Hampc. — Same as a Venezuelan speci- 

 men from Hampe : where described ? — On the rocky banks of streams. 



24. T. MACROSTEGiDM {sp. 710V.) : dioicum gregarium ; caule sim- 

 plici brevi gracili ; foliis e basi pellucide ampliuscule areolata longa 

 vaginante superne latiore undulata erecto-patentibus ovato-acuminatis 

 vel lanceolatis, pericha^tialibus longioribus margine flexuoso-involutis, 

 omnibus superne dense quadrato-areolatis apice plus minus serratis, 

 costa percurrente ; capsula anguste cylindracea curvula inclinata ; 

 operculo longissime aciculari capsulam superante ; perist. dentibus 

 longis leniter contortis atropurpureis papillosis filiscenti-attenuatis. — 

 On rocky banks. — The distinguishing characters of this species are, 

 the sheathing base of its leaves, particularly the perichaetial, the 

 remarkably long operculum, exceeding in length the slender, cylindi-i- 

 cal, inclined, and often horizontal capsule, and the finely attenuated 

 apices of the teeth of the peristome. 



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