MYCOLOGIA 



Vol. Ill November, 191 i No. 6 



THE AGARICACEAE OF TROPICAL 

 NORTH AMERICA— IV 



William A. Murrill . 



All of the tropical genera with rose-colored spores are treated 

 in this article. Those growing mostly on dead wood, like 

 Pluteus, are well represented ; while those growing normally in 

 the soil, like Entoloma, have few tropical species. The probable 

 reason for this has been discussed in a previous article. As 

 may be seen from the following key, only one of the genera is 

 provided with a volva, and this contains few species. None of 

 the species possesses an annulus. The principal characters used 

 in distinguishing genera are the attachment of the gills and the 

 consistency of the stipe, which may at times leave the position 

 of a species rather in doubt. 



Volva and annulus wanting. 



Stipe slender, cartilaginous. 



Margin of pileus incurved when young. 



Lamellae adnate or adnexed. 1. Leptoniella. 



Lamellae decurrent. 2. Eccilia. 

 Margin of pileus straight and appressed when 



young ; lamellae free or adnexed. 3. Nolanea. 

 Stipe fleshy, usually stout. 



Lamellae free. 4. Pluteus. 



Lamellae sinuate or adnexed. 5. Entoloma. 



Lamellae decurrent. 6. Pleuropus. 



Volva present, annulus wanting. 7. Volvariopsis. 



I. Leptoniella Earle, Bull. N. Y. Bot. Gard. 5: 424. 1909 

 Leptonia (Fries) Quel. Champ. Jura Vosg. 88. 1872. Not 

 Leptonium Griff. 1843. 



[Mycologia for September, 1911 (3: 207-269), was issued September 21, 1911] 



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