484 CLASS BASIDIOMYCETEAE 



they have in common the amyloid type of spore. For Irpex and Echino- 

 dontium see Polyporaceae (p. 494). 



Family Fistulinaceae. This small family of only a few species and 

 two, possibly more, genera is distinguished by its fleshy spore fruits and 

 by the separate though closely crowded hollow tubes which hang down 

 underneath the pileus. The latter may be centrally or laterally stipitate 

 in Fistulina, or resupinate in other genera. Each separate tube is formed 

 as an open cup which elongates and becomes lined internally by the 

 hymenium. If one would imagine hundreds of spore fruits of Solenia of 

 the Thelephoraceae arising from a common pileus the characteristic struc- 

 ture of this family would be realized. Fistulina hepatica Fr., the beef- 

 steak fungus, is found in nearly all temperate regions of the world on 

 oaks and other deciduous trees. The spore fruit is more or less fan-shaped 

 with a short, thick, lateral stipe. It is brown-red, blood-red internally, 

 and the closely crowded but separate tubes are reddish brown. When 

 young it is edible. Porothelium perhaps belongs here. It forms a resupinate 

 membranous or crust-like spreading hymenophore on which develop 

 numerous scattered wart-like projections which elongate, leaving a central 

 pore in each. This perhaps represents a connecting link between Solenia 

 and Fistulina. The relationship of this family to the Polyporaceae is 

 doubtful. Lohwag and Follmer (1936) and Elrod and Blanchard (1939) 

 studied the development of Fistulina and showed that its tubes are of 

 essentially the same structure as the cup-like spore fruits of Solenia and 

 Cyphella. There is no similarity in the development to the Boletaceae to 

 which the easily separable pores of the latter had suggested relationship. 



Family Meruliaceae. Like so many others of the Hymenomycetes 

 the members of this family are wood destroyers. The spore fruits at first 

 develop a smooth hymenium on which basidia develop to spore bearing 

 maturity. As this enlarges the surface produces low, rather thick folds 

 or ridges on the sides and rounded edges of which new basidia continue 

 to develop so that eventually basidia of all ages are to be found on the 

 ridges as well as on the intervening hymenium at the original level. The 

 ridges may anastomose so as to form a net-work, the pores that form the 

 meshes being shallow. Sometimes the ridges are more or less radiate or 

 may be interrupted. The spore fruits and the ridges are fleshy or waxy 

 or gelatinous. The low walls separating the pores do not necessitate their 

 pointing downward since air currents can carry off the spores when 

 discharged from the basidia regardless of the direction in which the pores 

 point. There is no agreement as to what genera should l)e included in this 

 family. Bourdot and Galzin (J 927) include seven genera, three of which 

 have a smooth hymenium (Coniophora, Coniophorella, and Jaapia), the 

 other four having projecting ridges or tubercles. Of these Phlehia is often 

 placed in the Hydnaceae and Plicatura (Trogia) in the Agaricaceae, 



