OF WESTERN PENNSYLVANIA 259 



On the ground, stones, rotten wood, stumps, etc. ; in moist 

 woods ; Europe, Asia, and from Labrador to the Rocky Moun- 

 tains and south to the \Yest Indies and South America. Very 

 common in the woods of our region. 



Allegheny : Fourteen pockets, various data, from the 



county, mainly O. E. J. or O. E. J. and 

 G. K. J.; Power's Run, September 14, 

 1905. O. E. J. and G. E. K. (Figured). 



Armstrong : Kittanning, "Buttermilk Falls," August 



22, 1903, and 1905. D. R. Sumstine; Kit- 

 tanning, September 24, 1904. O. E. J. 



Center : Tussey's Mt., above Shino-letown, July 15, 



1909. O. E. J. 



Clinton : Between Renovo and Haneyville, July 15, 



1908. O. E. J. 



Crawford Pymatuning Swamp, near Linesville, May 



10-11, 1906,' and August 3, 1909. O. E. J/ 



Fayette : Meadow Run Valley, four miles south of 



Ohio Pyle, September 1-3, 1906, Septem- 

 ber 1-3." 1907, May 30-31, 1908. O. E. J. 

 and G. K. I.; Ohio Pyle. July 4, 1904, and 

 May 14, 1905. O. E. J. 



Indiana : Along Cush-Cushing Creek, near Cherry 



Tree,\]uly 12. 1908. O. E. J. 



McKean : Bennett Brook, Bradford, February 21, 



1893. and Marilla Brook, October 22, 1896. 

 D. A. B. 



Westmoreland : Blairsville, July 12, 1903. Miss K. R. 



Flolmes ; slope of Chestnut Ridge above 

 Hillside, September 16-17, 1910. O. E. J. 

 and G. K. J. 



3. Thuidium recognitum [Hedwig] Lindberg. 



(Hypnmn recogn ituin Hedwig: T. dclicatitluin Bryologia Eu- 

 ropaea ) . 



(Plate XXXVI ) 



Yellowish-green, not as bright-colored as some of the other 

 Thuidiuuis, quite similar to the preceding but mostly bipinnate : 

 the primary branches are nearly equal in length, thus making 

 the general outline of the frond more linear-oblong; stem- 

 leaves usually about 0.6 to 0.8 mm. long, broadly triangular, 

 auriculate-cordate, abruptly acuminate, recurved-spreading 

 when moist, the apex acute and often very slender, the serru- 

 late margins usually plane, the leaves sulcate when dry ; costa 

 sub-percurrent, somew r hat broadened at apex : leaf-cells incras- 

 sate, and each with a long, slender, upcurved dorsal papilla, 

 the median rhombic-oblong to rounded-quadrate, the apical 

 somewhat narrower; branch-leaves with apical cells with 2-4 



