OF WESTERN PENNSYLVANIA 187 



a. Upper leaf-cells .007 to .CIS mm. in diameter; costa and lamellae 

 extending over one-fourth to three-fifths of the width of upper 

 half of leaf. c. 



b. Lamellae 3-6 in number and 3-6 cells in height, covering 

 about % to M of the upper leaf-width. 



1. C. undulata. 

 b. Lamellae 5-7 in number and 4-7 cells in height, covering 

 about % to Yi oi the upper leaf-width. 



la. C. undulata var. alle- 

 gheniensis. 

 c. Lamellae 5-8, 6-8 cells high, covering % to }^ of upper leaf- 

 width. 2. C. angustata. 

 c. Lamellae 6-8, 8-14 cells high, covering about 54 to J^ of upper 



leaf-width. 3. C. papulosa. 



c. Lamellae 7-12, 8-14 cells high, covering about ?^ to ^ of upper 

 leaf-width. 4. C. plurilamellata. 



1. Catharinaea undulata [Linnaeus] Weber and Mohr. 

 {Bjyum undulatum Linnaeus; Atrichum undulatuni Beauvois). 

 (Plate XXVI) 

 Loosely cespitose, dull, dark green: stems erect, ranging 

 from L5-6 cm. long, usually about 3-4 cm., mostly simple, 

 more or less gray-radiculose below, arising from a rhizone- 

 like base; lower leaves minute, increasing in size upwards, 

 the upper leaves lanceolate-lingulate, much crisped when dry, 

 transversely undulate when moist, sub-acute to obtuse, about 

 6-8 mm. long, 1 mm. wide, serrulate to the middle or slightly 

 below, the uppermost teeth double, strong, being inserted in 

 a border of 1-3 rows of brownish, pellucid to hyaline, incras- 

 sate, narrow cells ; the crests of the undulations on the back 

 of the leaf also often spinose in upper part of the leaf ; leaf-cells 

 elongate-rectangular at base, reaching about .017X-033 mm., 

 becoming quadrate towards leaf-middle, towards apex hexa- 

 gonal and somewhat longer transversely and about .017-024 

 mm. ; costa strong, ending just below apex, sharply dorsally 

 toothed, ventrally with 3-6 longitudinal lamellae which each 

 consist of 3-6 rows of cells similar to those of the leaf-blade, 

 the costa and its lamellae covering rarely more than one-fourth- 

 of the total leaf-width (in our region sometimes even nar- 

 rower) : seta erect, flexuose, somewhat sinistrorse, smooth, 

 lustrous castaneous, 2-5 cm. long; capsule lustrous, becom- 

 ing dull with age, castaneous, cylindrical, arcuate to almost 

 straight, inclined, smooth, about 4-5x1-1-3 mm.; peristome 

 single, the 32 teeth linear-lanceolate, obtuse, about 0.3 mm. 

 high, orange-pellucid along the median line, united in the 

 lower third into a reddish-orange basal membrane, the teeth 

 covered (especially along the margins) with a hyaline, densely 

 but minutely papillose layer which, during the winter, becomes 

 deciduous, thus leaving the teeth perfectly smooth; spores 

 smooth, orange, spherical, about .016-.019 mm. in diameter; 

 mature in late fall, operculum conic, curved linear-rostrate, 



