Holzinger : on the genus COSCInodon. 755 



this diagnostic character of C- raid, not offered a more distinct- 

 ive diagnosis of the species. In my diagnosis of the plant 

 under consideration I depended on Barnes' Key. Professor 

 Barnes himself did not recognize the character in his determin- 

 ation of the plant, which has the upper leaves at least furn- 

 ished with a slightly rough hyaline hair point much longer 

 than the leaf, which gradually decreases in relative length, 

 till near the rooting base of the stem the leaves are scale-like, 

 appressed to the stem, very small, and the costa in the lower 

 leaves cease below the rounded or barely apiculate apex. 



In this uncertain condition the matter has rested for nearly 

 two years. In May, 1896, I had the good fortune to col- 

 lect some mosses in Colorado, the home of the types of C. 

 wrighiii and C. rani- By the very kind and generous arrange- 

 ment of Professor Carl P. Baker, then of Colorado Agricultural 

 College, Fort Collins, I enjoyed the exceptional facility of col- 

 lecting for two days, with his guidance, and the use of a horse, 

 wagon and driver, in some of the side canons of Poudre river. 

 While we were drenched both days by an incessant rain, 

 and waded for miles up and down steep hills through the 

 stickiest and yellowest Colorado clay, we secured our mosses 

 all the more certainly because of the prevailing moisture. 

 Under these favoring conditions a number of species, mostly 

 very small mosses, were found by us on that trip; and among 

 them, fortunately, two species of Coscinodon. Pressure of 

 other duties has prevented me from working out this 

 puzzle till recently. There is no difficulty at all in distinguish- 

 ing the two species from each other with the naked eye, when 

 one is sure of the genus from the presence of the mitrate, 

 plicate calyptra. The gross distinction is as follows: 



1. Coscinodon wrighiii is silvery green, from the presence 



of the much lengthened hair points on the upper 

 leaves, which stand erect; and this, with the more 

 crowded condition of the plant, which forms small 

 dense cushions, gives the lighter color. 



2. Coscinodon raid has a more decided green tinge, there 



being fewer long hairs; the plants occur also usually 

 less crowded, and in more extended patches. 



In order to determine whether there was some tangible dif- 

 ference observable with the pocket lens, I moistened and sep- 

 arated several dozen plants of each species, washed out the 

 sand and clay in which they are uniformly imbedded nearly to 



