396 
OrTHOTRICHUM soRDIDUM, S. & L. in Austin’s Musci App. 168 
(1870). 
Sullivant, Icones Supplement, 67, t. 49 (1874). 
This species comes very close to O. fastigiatum, as described 
by Limpricht, agreeing with it in the trabeculate and striolate 
teeth. The form given by Sullivant (I. c. fig. 10) is seen occa- 
sionally, but the teeth are as often trabeculate at apex, as figured 
by Limpricht, even in James’ own specimens from Cambridge, 
Mass., which are the ones referred to by Sullivant in the Icones. 
My experience is, that in the older capsules the delicate trabecu- 
late apex of the teeth is broken off, and they appear as figured in 
the Icones, though I have seen on one capsule teeth of both kinds. 
Limpricht makes a point in the position of the stomata to distin- 
guish O. fastigiatum, stating that they are few around the base of 
the spore-sac, whereas in O. affine he says they occur in two 
rows around the middle of the theca. I find in O. sordidum that 
they are usually median as in O. affine, but I have seen them both 
in one row and two. The cilia in O. sordidum seem always regu- 
lar, not appendiculate. The capsule is more immersed and more 
regularly ovoid when mature, before it becomes sulcate, and the 
neck is shorter and more suddenly contracted, and almost always: 
immersed and invisible in O. sordidum, while in American speci- 
mens of QO. fastigiatum, collected at Lake Superior, by Macoun, 
the neck is almost entirely exserted. I do not understand why 
Venturi refers O. sordidum to the section of QO. arcticum, as its 
alliance seems to me to be entirely with the species with which 
I have compared it, and its range is from Closter, N. J., al 
most at sea level to Kent county, New Brunswick, though it has 
been collected at Dixville Notch, N. H., by T. P. James; the 
original station being at Cambridge, Mass. The leaves also 
-have the nodose, or porose lower cells, which are specially de- 
scribed by Limpricht in O. affine and O. fastigiatum. 0. sordidum, 
‘though, seems to be more allied to O. affine in its leaves, for the 
lower cells have thickened walls, the ends in some cases project 
‘ing into papilla, bringing two adjacent ends together so that the 
‘papillz appear double; this gives this species a very characteristic 
“appearance, which I have not observed in either of the others, a5 _ 
-the base of the leaves is usually smooth and free from papilla, 
