92 HYPNACEAE 



Key 



I — Capsules 3 to 4 times as long as broad; median leaf cells 10 times as 



long as broad dendroides 



Capsules 5-6: 1 ; median leaf cells not more than 7:1 2 



2 — Plants of a distinctly tree-like habit; median leaf cells 5-7: 1. 



Americanum 

 Plants growing in dense tufts so that the tree-like habit is obscured, 

 or prostrate and hypnoid in appearance; median leaf cells 2-3: 1, 



Kindbergii 



C. Americanum Brid. Frequent on soil in moist shaded 

 places but fruiting sparingly. Autumn. 



C. Kindbergii (R. & C.) Grout. Common in swamps, often 

 growing in water. Autumn. 



C. dendroides (L.) Web. & Mohr. Yonkers, E. C. Howe, 

 Bx!; "in swamps about Closter, N. J.," Muse. App. 286. 



Subfamily Porotricheae 



Plants dendroid in habit. Leaf cells short and broad. 

 Capsules unsymmetric and inclined, with a perfect hypnaceous 

 peristome. Brotherus in "Die Natiirlichen Pflanzenfamilien " 

 puts this subfamily in the Neckeraceae, an arrangement with 

 which I am compelled thoroughly to disagree. All the char- 

 acters, of our species at least, are hypnaceous except, possibly, 

 the areolation. We have one genus, 



POROTRICHUM Brid. (Thamnium B. & S.) 



P. Alleghaniense (C. M.) Grout. Palisades, N. Y., R. S. 

 W. Bx!; deep shaded crevices in wet rocks, Closter, N. J., 

 Austin, Bx!; "Palisades, not rare," Muse. App. 337. 



Subfamily Amblystegieae 



Plants of various habits and habitats. Central strand and 

 costa nearly always present (except Campylium species). Para- 

 phyllia rarely present (except in Cratoneuron) . Seta smooth, 

 capsules oblong to subcylindric, cernuous, more or less curved 

 and unsymmetric, usually contracted under the mouth when 

 dry and empty. Leaves acute to slenderly acuminate (except 

 Calliergon) . 



