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and Stereocaulon, and Sphaerophorus compressus, which cover the ground and the 

 rocks and the tree trunks. In the sparsely wooded areas, in other words where 

 there is plenty of light and sunshine, trees are literally covered with Usnea species, 

 and Theloschistes flavicans, the bright yellow of the latter standing out in marked 

 contrast to the former. It was indeed a treat to see such fine specimens of the 

 Theloschistes, most of them many inches long; they varied in shades of color, 

 from light yellow to some of a deep orange. Along the trails through the thickly 

 wooded regions, Usnea is restricted to the tree tops, and one is hardly aware of its 

 occurrence. If, however, a walk is taken on a day following a windy, rainy night, 

 there will be evidence enough of its presence, in the bits strewn along the trail. 

 The tree top species seems to be almost always U. florida, but, in the more open 

 places, where the trees are covered, one finds not only U. florida but also U. dasy- 

 poga, U. ceralina, and U. rubiginea. Three species of Ramalina were collected, all 

 in the garden of Cinchona : R. linearis, R. denticulata, and another still to be deter- 

 mined. Of species of Cladonia, more than 30 were collected; here will be men- 

 tioned only the most common and interesting ones. To me, the most interesting 

 one was C. aggregata, and its variety straminea. This Cladonia was found almost 

 everywhere, especially on moist, poorly illuminated slopes. Its color, size, and 

 general appearance varied greatly; so much so, that one is inclined to think that 

 instead of but one variety, we have here at least three or four. Its peculiar 

 structure interested me right from the start, and I wondered if the holes in the 

 sides of the podetia enabled the plant to absorb and perhaps retain more water 

 than other species of Cladonia not having them can do. To see if this were so, 

 I weighed off i gram of the air-dried plant, and found that it could absorb, and 

 retain i.io grams of water, in other words, in case of rain, it could increase its 

 weight 110%. The same experiment was tried with C. pycnoclada, which de- 

 lights to grow under extreme xerophytic conditions, and I was rather surprised 

 to learn that it could absorb and retain twice its. weight of water; in other words, 

 increase its weight 200%. No attempt was made to go deeper into this interesting 

 problem, but enough was done to show that the holes did not assist in increasing 

 the plant's power to absorb water. In all probability they are for aeration. C. 

 aggregata is hygrophytic, the holes probably serving the plant to dispose of water. *^ 

 While on this subject, I will add that a gram of Slicta aurata increased its weight 

 300%; that is, it absorbed and retained three times its weight of water, and Lepto- 

 gium hullatum absorbed and retained four times its weight of water. 



To return to the Cladonias, both C. pycnoclada f . flavida, and f. exalbescens 

 were found, both on exposed sunny slopes, forming patches of wonderful size. 

 Another Cladonia that is sure to attract attention, on account of its beauty, its 

 large size, and prevalence, is C. sqtiamosa f. phyllocoma; it was at home along the 

 shady trails. Other Cladonias, of more or less interest are the following: C. 

 ceratophylla, very common; C. dactylota; C. decoriicata; C. didyma, quite common 

 on rotting logs; C.foliacea (?), very common; C. furcata i. foliolosa-, C. hypocritica 

 (?); C. peltasiica\ C. pilyrea; C. rangiformis. 



It would be worth while to study Cladonia retipora, in this connection. 



