208 Transactions of ilie Society. 



A. homhyeinus, the first thing I did on receipt of tlie specimens was to 

 look for the cystidia. For several hours of the night my efforts to find 

 anything were unavailing ; at last I saw one, soon afterwards two others 

 (in the hymenium), at length two more ; they all agreed exactly in their 

 great size (longer than any here illustrated), in their spindle shape, and 

 in being without spicules at the summit. The cystidia must be ex- 

 tremely rare in A. homhyeinus, and this fact will give some one a good 

 opportunity for saying he cannot see them, or for some rash person to 

 deny their existence altogether." In a section of the hymenium these 

 bodies, when present, are easily known by their large size, usually pro- 

 jecting much beyond the basidia with their spicules and spores. When 

 young the cystidia, which may be considered as the growing points of 

 latex vessels or hyphae, contain hyaline protoplasm and a large nucleus 

 with a nucleolus — corresponding to the nuclei present in other parts of 

 the laticiferous system — but when they have attained their full size the 

 protoplasm is replaced by a finely granular substance containing gly- 

 cogen, which eventually escapes through a nipple-like or filiform at- 

 tenuation at the apex of the cystidium. In some species four or more 

 of these attenuations are present, and arranged in a similar manner to 

 the spicules surmounting a basidium, which has led to the idea on the 

 part of some that cystidia may be abortive basidia. In the young 

 hymenium cystidia may be met with in all stages of development, and 

 are always cut off by a septum from the vessels they terminate, at which 

 point they break away and drop off after the escape of their contents. 

 As to their function, nothing definite can be stated, but I am inclined 

 to believe that their contents are poured out for the purpose of supplying 

 a certain amount of food to the developing spores, which in many species 

 are bathed with it during growth. 



Laticiferous vessels are by no means confined to the above-named 

 genera, but are widely distributed throughout the order, being especially 

 well developed, and containing abundance of latex, in Peziza saniosa Fr. 

 Neither do 1 consider the whole of the latex as consisting of glycogen, 

 but that it is present in the laticiferous vessels along with other sub- 

 stances, being especially abundant during the early stages of the plant's 

 development, and replaced later on by a substance assuming a blackish- 

 brown colour with iodine or dilute sulphuric acid, which does not change 

 when heated. 



