324 SUMiMAilY OF CURKENT RESEARCHES RELATING TO 



tlie pistil of the diseased flower is larger than the healthy pistil, but the 

 stamens are much reduced in size and have a pale yellow colour, the 

 healthy anthers being green. The whole diseased head is slimmer and 

 has an olive-green colour, and the fatid odour is apparent at an early 

 stage. The conditions are noted at each stage of growth. Finally, at 

 maturity the smut mass in the kernels becomes a mouse-brown colour 

 and is pasty. 



Superposition of Fungi.*— It is not unusual to find a Hymeno- 

 mycete growing on the pileus of another, generally the same species. 

 P. M. Biers figures and describes two such instances, the one of Boletus 

 edidis, the other of Clitocybe nehidaris. In the latter case the 

 superposed Agaric is as well formed as the individual on which it rests, 

 and to it are attached the basal mycelial strands that prove it to be an 

 independent growth hoisted up 'by the other, but not in continuitv 

 with it. 



Origin and Development of Lamellae in Coprinus. t — <^^^. F. 

 Atkinson describes the very early stages of Coprinus as being in the 

 form of irregular tubercles scattered on strands of the mycelium ; it 

 was only at a later stage that difi'erentiation of tissues could be 

 observed. Atkinson's study is not of these early stages, but of the 

 formation of lamelljB. The primordium of the pileus grows in a radial 

 direction both upward and in a lateral and slightly downward direction, 

 and growth is more rapid in the lateral centrifugal direction ; the hyphse 

 also are richer in protoplasmic content. The zone of radial hypha? 

 enveloping the pileus he calls the blematogen, a tissue that varies with 

 the different species ; thus in C. micaceiis it becomes free from the pileus 

 in mica-like flakes. 



The prelamellar cavity arises by a tearing apart of the plectenchyma 

 in the angle between the pileus and stem " fundaments," due to tension 

 resulting from difi"erences in rapidity of growth. The palisade layer of 

 the young hymenophore begins its formation at or upon the apex of the 

 stem and then proceeds outward, over the under-side of the pileus. 

 The lamella3 originate as downward projecting salients of the palisade 

 tissue, in a series radiating outward toward the margin of the pileus, 

 the younger portion being always towards the margin ; they increase in 

 width by apical and also by intercalary growth. 



_ The attachment of the gill margins to the stem takes place after the 

 origin of the gills, beginning where their margins come in contact with 

 the stem, or with the fundamental plectenchyma surrounding the stem. 

 Attachments may begin early or late according to species ; there is an 

 interlocking of hyphaj, and also an interwedging of the marginal cells of 

 the gills and trama with the surface cells of the stem. 



The cystidia have not been thoroughly studied, but it was observed 

 that in G. airammtarius they arose from cells of the trama beneath the 

 subhymenium. 



* Bull. Soc. Mycol. France, sxxi. (1915) pp. 14-19 (2 figs, and 1 pi.), 

 t Bot Gaz., Ixi. (1916) pp. 89-130 (6 diagrams and 8 pis.). 



