LITTLE JOURNEYS INTO MOSSLAND 



XL — A February Thaw 

 George B. Kaiser 



The winter which followed my first acquaintance with Dicranella and Cath- 

 arinea was a severe one. The mantle of snow long lay deep and protective over 

 bank and hillside, and the woods were hushed, save for the subdued twitter of 

 the juncoes, or the occasional chatter of the squirrels far overhead in the branches 

 of the oaks. The valley of the Wissahickon extended in frozen beauty. The 

 stream was changed into ice, which was dark green like the surrounding hem- 

 locks and along the driveway great ribbed icicles depended from the rocks. 

 The tinkle of sleighbells often resounded there in the short afternoons of January. 



In mid-February came a great thaw. For several days rain fell inter- 

 mittently from dark, lowering skies. Town and country were deluged with 

 slush. Then, one morning, the sun broke through the clouds and spread warm 

 golden beams over all the earth. The air was like a breath of spring. Pulling 

 on a pair of sturdy arctics it was little more than a half hour's journey to the 

 Wissahickon Creek. The decaying ice of the stream, here and there broken, 

 was submerged. Still there was plenty of snow, but enough had thawed or 

 been washed away to expose many a mossy bank. What a Mecca for the bry- 

 ologist and what a treat for the lover of the beautiful! My mind's eye this 

 day beholds the golden green of Cirriphyllum Boscii, which used to be included 

 in the important genus Eurynchium. The swollen stems of this pleurocarpous 

 species had been inexpressibly freshened by the rain and warm atmosphere 

 and peeped out at the edge of the snow like a miniature low-lying arboretum of 

 exotic evergreens. Neither before nor since have I seen greater beauty in this 

 Cirriphyllum which I came to know that day for the first time. 



Then, too, here and there in bare spots the now pale green pin-cushions of 

 Leucobryum glaucum studded the thawing snow. When we microscopically 

 examine these leaves we better understand how the thin layer of chlorophyll 

 overspread with tissue shows plainly when the plant is moist and the over- 

 lying tissue is transparent, but how the plant appears white when the tissue is 

 dry and consequently opaque. In company with Leucobryum were larger 

 clumps of the broom fork moss, Dicranum scoparium, with glossy secund leaves. 

 Some of us remember this Dicranum in our boyhood — long before we knew 

 its proper name — gracing the space beneath our Christmas tree, with bits of 

 glass among the clumps of moss to look like pools, and on these bits of glass toy 

 ducks, a sight which filled our childish eyes with pleasure. 



That day three common species of Mnium were at their aesthetic best in 

 vegetative luxuriance, although their sporophytes were but spears, lacking two 

 months to maturity, Mnium cuspidatum, here the commonest, displayed 

 dainty stolons with broad leaves characterized by serrations passing halfway 

 down the margin; while the larger Mnium affine ciliare, with sometimes clus- 

 tered fruit, also stoloniferous in growth, showed long marginal teeth prominent 



