40 



MOSSES WITH A HAND-LENS 



Figure is. 



Ceratodon purpureus X ^ 

 and capsule 



. Leaves, calyptra, 

 X 10. 



The leaves may be 

 entire or slightly denticu- 

 late at apex, and the costa 

 is sometimes percurrent 

 or even excurrent. The 

 stems sometimes become 

 three inches long in 

 shaded places. 



When the capsules 

 have fully matured they 

 shrink when dry and be- 

 come furrowed. This pe- 

 culiar furrowing and the 

 dark rich color of the 

 capsules, a color called 

 purple by the older bot- 

 anists but which is really 

 a very dark chestnut or 

 red-brown, make it easy 



to recognize. The peristome is shown in Plate II. 



Aulacoinnhim pabistrc has a capsule furrowed in a similar 

 manner, but it is easily distinguished by the characters noted 

 under the description of that genus. 



TREMATODON Mx. 



T. AMBIGUUS (Hedw.) Hornsch., the 

 Long-necked Moss, is so odd in appear- 

 ance that it will need little description. 

 It is not common, but will be met with 

 occasionally in rather dry soil in copses 

 and old fields where the grass is thin. Be- 

 sides the long neck, the bright yellow 

 setae, closely resembling those of Dit- 

 riehum pallidum, are an additional aid 

 in identification. The capsules mature 

 in summer. 



T. LONGicoLUS Mx. is easily distinguished by its much longer 

 neck, twice the length of the rest of the capsule, which is more 

 cylindric than in T. ambiguus. Moist clayey or sandy soil in 

 the southern part of our range and southwards. 



Trematodon ambiguus 

 XI, and capsule X5. 



