30 DICRANACEAE 



"Northport.Sanial," Flora L. Id.;S.Id., E. G. B., Bx! Autumn- 

 winter. 



D. Schreberi (Schrad.) Schimp. "Wet rocks and banks, 

 Hohokus, N. J.," Muse. App. 77. According to N. Am. Flora 

 Austin's specimens are var. robusta Schimp. 



Subfamily Dicraneae 



Common plants, large and often somewhat branched ; some of 

 the rarer species are small. Leaves narrowly lanceolate, often 

 falcate-secund; cells at the angles enlarged, often inflated, hyaline 

 or colored. Operculum usually long-beaked. 



DICRANUM Hedw. (Plate III, Fig. 1.) 



Leaves smooth (papillose in spurium, montanum and occa- 

 sionally in pallidum); lower cells rectangular, angular conspicu- 

 ously dilated. Capsules on a straight erect seta, erect or in- 

 clined; teeth red, cleft half-way into two or occasionally three 

 segments, vertically striate below with fine lines. 



The Dicrana of our region are one of the most common and 

 beautiful elements in woodland scenery. They are, for the most 

 part, bright yellow-green and grow in wide thick tufts or mats. 

 The leaves are frequently more or less secund. They are com- 

 mon on the ground, stones, rotten wood, and sometimes they 

 occur on the base and trunks of trees. Most Dicrana mature 

 their spores in autumn, but more observations are needed to 

 give exact dates for each species. 



Key 



1 — Capsule cernuous, more or less arcuate 2 



Capsule erect, symmetric 9 



2 — Upper leaf cells longer than broad, porose 3 



Upper leaf cells not porose, nearly as broad as long 5 



3 — Capsules clustered, leaves strongly transversely undulate, silky. 



undulatum 



Capsules solitary 4 



4 — Leaves transversely undulate when moist, slightly or not at all 

 secund, costa often without lamellae at back; plants dull or pale 



yellowish green Bonjeani 



Leaves not at all undulate, secund, with strongly serrate lamellae 



at back scoparium 



5 — Leaves strongly papillose at back, little or not at all secund .... spurium 

 Leaves not noticeably papillose (sometimes papillose in pallidum) .... 6 



