16 TIMBEE EOT CAUSED BY LENZTTES SEPIAEIA. 



importance, since it means tliat decayed timbers are a constant 

 source of infection and should be destroyed instead of being left lying 

 upon the ground. 



The number of spores produced by an ordinary-sized sporophore 

 of Lenzites sejnaria is hterally milUons. Buller (1909) has shown 

 that a sporophore of Daedalea confragosa (Bolt.) Pers., about 2 

 square inches in area, produced nearly three-fourths of a billion of 

 spores when revived after desiccation. This is much like Lenzites 

 sejnaria in the character of its sporophores and may be taken to 

 indicate very roughly the conditions occurring with the latter species. 

 This empliasizes the fact that where there are fruiting bodies of 

 Lenzites sepiaria there surely are spores everywhere in the vicinity, 

 and no timber can be expected to remain free from them for any 

 great length of time. Hence, it is doubly wise to destroy all decayed 

 timbers. 



DEVELOPMENT OF THE SPOROPHORES. 



The first visible sign of the effects of this fungus is a blackening 

 of the ends of the affected timbers over a space of several square 

 inches. This blackening is quite noticeable to a close observer, and 

 is present for some httle time before the mycelium appears on the 

 surface. After a few weeks, when there is sufficient moisture in the 

 air, a tiny tuft of white mycehum appears somewhere on the black- 

 ened area. This grows larger wdtliin a few days if the moist condi- 

 tion continues, until it is about one-fourth inch across; then the tuft 

 thickens until it stands out from the surface of the wood about one- 

 eighth inch. The development of the gills begins early, goes on 

 rapidly, and continues until the sporophore has reached its growth. 

 The o-ills bet^in to form while the mycelial mass is still small (one- 

 eighth to one-sixteenth inch), as soon, indeed, as there is room for a 

 gill to be formed beneath. When the gills are well started, and 

 sometimes before, the older parts of the mass turn to a light-brown 

 color, meanwhile passing through the various sluules of yellow. In 

 Texas the entire development of the mature fruiting body may take 

 place within 10 days from the very first appearance of the mycelium 

 on the outside of the timber. After the first sporoplioiv has formed 

 it is usually not long before several others are produced innnediately 

 adjacent to it. 



Some notes made by the writer on the rai)idity of the growth of 

 the sporophores in Texas are of interest. On one timber several tiny 

 masses of white mycehum were barely visible on one of the black- 

 ened spots at the end of the timber. Seven days later the gills were 

 beiiinnini: to form, and the oldest parts had turned brown. On the 

 eleventh day several distinct sporopliores which had formed (Uirmg 

 this time had fused into a single one, three-fourths inch long and 



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