180 BULLETIN OF THE UNIVERSITY OF WISCONSIN. 



DICHODONTIUM, p. 61. 



Capsule strumose D. Olympicum, 54. 



Capsule not strumose. 



Costa vanishing below apex, seta yellow . . D. pellucidum, 1 62. 



Costa percurrent, seta red ]). Canadense, 62. 



TREMATODON, p. 62. 



Leaves lance-subulate. 

 Collum equaling or somewhat exceeding the oval oblong 



sporangium, teeth deeply bifid . . . T. ambiguum, 63. 

 Collum greatly exceeding the cylindric sporangium, 



teeth perforate T. longicollis, 63. 



Leaves ovate, short pointed, teeth entire or perforate T. brevicoJlis, 55. 



DICRANELLA, p. 64. 



I. Cells of the exothecium rectangular quadrate; seta red; costa 

 usually narrow and well defined below. 



A. Leaves not sheathing, erect-spreading. 



Costa percurrent or excurrent. 

 Annulus none, peristome papillose. 

 Leaves short acuminate, blunt, costa ^ width of leaf 



at base D. Langloisii, 58. 



Leaves long acuminate, costa ^ width of leaf at base D. Howei, 61. 

 Leaves long acuminate, acute, costa | width of leaf at base. 



Capsule cernuous ....... D. varia, 65. 



Capsule erect, symmetric .... D. rufescens, 66. 



Annulus present, peristome not papillose. 



^ Teeth orange, pale at the apex, costa excurrent . D. parvula, 57. 



Teeth purple, costa percurrent . . D. leptotrichoides, 59. 



Costa ceasing within the apex, annulus large, simple 8 D. debilis, 66. 



B. Leaves from a sheathing base, squarrose. 



Broad, obtuse ....... D. squarrosa, 65. 



Abruptly subulate. 



Capsule striate, substrumose, leaf apex entire . D. Grevilleana, 64. 

 Capsule not striate nor strumose, leaf apex serrulate D. Schreberi, 64. 8 



1 See also Appendix, no. 53. 



2 As near as can be determined Z>. laxiretis R. & C. faDs here. See Appendix, no. 62, 63. 

 See Appendix, no. 56. 



