2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. J'Z 



DICRANACEAE 



CERATODON PURPUREUS (L.) Brid. 



Nos. 2391 f, 3393b, 34140. Mostly fruiting. The capsules are 

 frequently subsymmetrical, very little strumose, and only lightly 

 plicate, as I have found also in specimens collected by Scott-Elliot 

 in Central Africa ; but these characters are far from constant and 

 may indeed be pathological. 



HOLOMITRIUM MACLENNANI Dixon, sp. nov. 



(PI. I, fig. 2.) 



Sat robustum ; habitu H. crispidi Mart, brasiliensis ; laxiuscule 

 caespitosum, pallide olivaceo-viride. Caulis rigidiusculus, dcnsifo- 

 liits, circa 3 cm. altus, parce divisus ; folia e basi erecta ovata sub- 

 vaginarite squarrosa, siccitate crispula, undulata, suberecta, superne 

 in acumen latiuscnlum actum sensim angustata. marginibus inferne 

 revolutis, supra dense argiitequc et grosse inaequaliterque dcntata: 

 costa sat valida, infra apicem desinens ; cellulae superiores ovales, 

 dorso papillis immerosis dense scabendae; basin versus sensim 

 elongatae, infimae aurantiacae, laeves, juxtacostales lineares, margi- 

 nem versus latiores, breviter rectangulares, pellucidae, ad alas de- 

 currentes pcrpaucae paiillo dilatatae indist'mctae. 



Seta I -1. 5 cm. alta, foliis perichaetialibus peraltis, circa tertiam 



partem setae saepe attingentibus, convolutis. Theca subcylindrica, 



'circa 3.5 mm. longa. Peristomium e dentibus irregnlaribus inacqiiali- 



hiis, in crura plura inacqualia, longa, pallida, brevissime interne 



nodosa fissis instructum. Annulus multiplex. 



Hab. : Heath Zone, 12,000 ft., epiphytic, rare; No. 3445. 



A fine species, dififering in the coarsely toothed, broadly pointed, 

 squarrose leaves from all the African species except H. acutum 

 Wright, to which it is allied; that species, however, has' the leaves 

 more narrowly pointed, less sharply serrate, and with the base less 

 widely vaginant, and the perichaetia are much shorter. The peri- 

 stome teeth here are more or less equidistant, but very variable, some- 

 times showing a tendency to approximation in pairs ; they are very ir- 

 regular, but the capsules are overripe and it is difficult to know how 

 much of the irregularity is due to wear. Each tooth is made up of 

 two, three, or more vertical, filiform, red laminae, more or less 

 coherent, without transverse bars below, and without striolations ; 

 above they are pale, and closely articulate with shortly protuberant 

 internal nodules. 



