( 48 ) 



18. DRUMMONDIA, Hook, 

 clavellata, Hook. Bark of trees. 



19. ORTHOTRICHUM, Hedw. 



1. obtusifolium, Schrad. Trees. 



2. strangulatum, Beauv. Trees. * 



3. Canadense, Br. & Schimp. Trees. 



4. Ludwigii, Schwaegr. Trees. 



5. Hutchinsise, Smith. Trees, &c. 



6. crispum, Hedw. Rocks. 



20. SCHISTIDIUM, Br. & Schimp. 

 apocarpum, Br. & Schimp. Rocks. 



21. GRIMMIA, Ehrh. 



1. Olneyi, Sulliv. Rocks near streams. 



2. Pennsylvania, Schwaegr. Rocks and stones. 



3. Donniana, Smith. Old stone walls. 



22. RACOMITRIUM, Br. & Schimp. 



1. aciculare, Brid. Mountain streams. 



2. fasciculare, Brid. Moist rocks. 



3. eUipticum, Br. & Sch. Moist rocks. 



23. HEDWIGIA, Ehrh. 

 ciliata, Ehrh. Rocks and bowlders. 



24. BUXBAUMIA, Haller. 

 aphylla, Haller. Around stumps in woods. 



25. DIPHYSCIUM, Web. & Mohr. 

 foliosum, Web. & Mohr. Clayey, or barren soil. 

 26. ATRICHUM, Beauv. 



1. undulatum, Beauv. Moist clay banks. 



2. angustatum, Beauv. Shady woods and swamps. 



3. crispum, James. Banks of streams. 



27. POGONATUM, Beauv. 



1. brevicaule, Brid. Moist clayey banks. 



2. urnigerum, Brid. Mountains. 



28. POLYTRICHUM, Brid. 



1. commune, L. Shady moist places. 



2. formosum, Hedw. Base of trees in woods. 



3. Juniperinum, Hedw. Margins of woods. 



4. piliferum, Schreb. Rocky places. 



29. AULACOMNIUM, Schwaegr. 



1. heterostichum, Br. & Sch. Shady banks. 



2. palustre, Schwaegr. Swamps. 



