48 TEXT-BOOK. OF FUNGI 



hymenium, the surface of which consists of their closely 

 packed free ends, and a section through the hymenium 

 shows the elongated cells of basidia and paraphyses closely 

 packed side by side like the palisade cells of a leaf. The 

 functions of paraphyses are not known. In the Basidiomy- 

 cetes they originate from the same hyphae that produce 

 basidia. 



(3) Cystidia, or single cells, usually larger than basidia, 

 and often projecting much beyond the level of the hyme- 

 nium. Cystidia are present in some species and absent in 

 others. As a rule they are more general in the older or 

 primitive types of the Agaricaceae, as in Coprinus and 

 other dark-spored genera, than in the modern white-spored 

 types, as Tricholoma, Amanita, etc. Cystidia are more 

 general, and undergo greater modifications of form in the 

 older families of the Basidiomycetes, as the Thelephoraceae 

 and Polyporaceae, than in the Agaricaceae. Regarding the 

 functions of cystidia but little is definitely known. It has 

 been suggested that they prevent the removal of the spores 

 from the hymenium by slugs, snails, etc. In the genus 

 Coprinus^ where the cystidia are very large and conspicuous, 

 they were considered at one time to represent male sexual 

 organs. De Bary states that in Lactarius deliciosus and 

 allied species the cystidia are filled with densely granular 

 contents, and resemble the laticiferous tubes, and in thick 

 sections look as though they were branches of these tubes, 

 but closer observation showed that they sprang as branches 

 from non-laticiferous hyphae. This statement, however, 

 is not correct. I have described and figured cystidia in 

 Lactarius and Russula as terminating laticiferous hyphae. 

 Biffen has also described cystidia as terminations of the 

 conducting system in Collybia velutipes, where they can be 



