—44— 

 The Weissias growing on trees usually grow in more rounded tufts 

 with the leaves more crisped when dry than is usual with Ortho- 

 trichum growing in similar situations. The books all say that the 

 hairs on the calyptra of Weissia are tlexuous, and those on Ortho- 

 trichum straight, but this distmction appears to be rather too fine 

 for the amateur to profit by it. The capsules in both genera are 

 erect and symmetric and quite regularly striate when dry with 

 eight or sixteen ridges and as many alternating furrows. These 

 ridges consist of cells larger, darker, and thicker- walled than the 

 alternating tissue. The seta in Orthotrichum is so short that the 

 capsule is nearly always partially immersed ; in Weissia the seta 

 is long enough to exsert the capsule entirely beyond the perichee- 

 tial leaves. 



Orthotrichum is a very large and difficult genus, and cannot 

 be successfully treated in a book of this kind. Weissia is a small 

 genus whose species are easily recognizable without any lens 



whatever. 



The Puckered Weissia has pear-shaped capsules, abruptly 

 narrowed to the very small mouth ; the ridges and furrows extend 

 only a short distance around the mouth of the capsule, giving it 

 the peculiar and characteristic appearance shown in the cut. 



The capsules of the Crisped Weissia have a much larger mouth 

 and are striate for the entire length. The seta is shorter, the color 

 is lighter, and the tufts are rather thicker than in the Puckered 

 Weissia. In a not uncommon variety of the Crisped Weissia the 

 capsule is much shorter and is suddenly contracted into a neck, 

 narrow and much twisted when dry. These two species grow 

 exclusively on trees; the third, the American Weissia, grows exclu- 

 sively on rocks. Its leaves are rigid when dry like those of Ortho- 

 trichum, not crisped as in the two tree-growing species; the cap- 

 sules very closely resemble those of the Crisped Weissia. 



AH three of the Weissias are common in the hilly regions of 

 our range. They mature their capsules in autumn or early win- 

 ter, but apart from the calyptra are more characteristic when dry 

 and empty. The tree- growing species furnish good coUectmg for 

 winter and early spring, when most other mosses are buried under 



the snow. 



Weissi.4 EiiRH.=Ulota Mohr. 



The Puckered Weissia= H^. coarctata (Beauv.) Lindb.= 67tf/fl 



Ludwii^ii Brid. 

 The Crisped W.= W. nlophylla YMx\\.^Ulota cnspa Brid. 



variety^ W. ulophylla crispula\'&xnch) Hammar 



== Ulota cr/spiila Brid. 

 The American Weissia= W. Americana (Beauv.) \J\vAh.= Ulota 



HutchmscE Schimp. 



*From " Mosses With a Hand-lens," by permission. 

 Brooklyn, N. Y. 



