300 



RESEARCHES ON FUNGI 



(3) The interlamellar spaces between the gills, which are re- 

 quired to render possible the free development of the spores on the 

 hymeniura, are secured by the cystidia which act as distance-pieces. 

 In the young and unexpanded pileus the cystidia bridge the 

 interlamellar spaces. This arrangement is similar to that of the 

 Atramentarius Sub-type. 



(4) The interlamellar spaces do not continue to be bridged by the 

 cystidia during the discharge of the spores. Before the process of spore- 

 discharge begins, the 

 pileus expands um- 

 brella-wise and ad- 

 jacent gills become 

 w i d e 1 y separated 

 from one another, so 

 that the cystidia no 

 longer bridge the 

 interlamellar spaces 

 but merely project 

 from the gill-sides 

 like pegs. In this 

 respect the Lagopus 

 Sub-type forms a 

 marked contrast 

 with the Atramen- 

 tarius Sub-type. 



(5) The basidia are dimorphic, for they are of two lengths, long 

 and short. In this character there is an agreement with most of 

 the other Coprinus Sub-types but not with the Micaceus Sub- type 

 where the basidia are tetramorphic. 



(6) The pileus-flesh covering the gills is membranous. When 

 the pileus expands just before spore-discharge, the flesh splits along 

 radial lines corresponding with the lines of attachment of the gills, 

 and each gill becomes split a certain distance down its median 

 plane. Thus on the top of the pileus there comes into existence a 

 series of radial sulcations which stretch from the pileus-rim to the 

 disc. These radial sulcations do not arise in Coprinus atramentarius 

 and certain other fungi of the Atramentarius Sub-type. 



Fig. 130. — Coprinus lagopus. Fruit-bodies of medium 

 size coming vip spontaneously on liorse-dung balls 

 in the laboratory at Winnipeg. The stipes are 

 elongating. The spores on the gills have become 

 pigmented, hence the dark colour of the pilei. 

 Natural size. 



