i66 Transactions British Mycological Society. 



may differ in several respects from the typical species. With 

 regard to the former, for ordinary systematic purposes the use 

 of the usual spore-cast provides a sufficiently good safeguard, 

 although the possibility of obtaining exceptional spores is not 

 excluded by this method (see, for instance, these Trans, vol. iv. 

 pp. 298-300). With reference to strains, the existence of these 

 in many parasitic species has been definitely proved, and though 

 perhaps less general it occurs also amongst the Hymenomycetes, 

 as has been shown with respect to the formation of fruit-bodies 

 in Schizophyllnm commune and Stereum purpureum (Naturwiss. 

 Zeitschr., 1909, p. 521). It will be noted that the fungi alluded 

 to above (Fusarium, etc.) are Hyphomycetes and it would 

 appear that, owing perhaps to the great diversity of substrata 

 on which they exist, they are more liable to vary than the 

 Hymenomycetes. 



The list as given in the present revision consists of 37 species. 

 Two of these, C. Broomei and C. Invalii, we have been compelled 

 to describe as new, and four other novelties were described 

 daring the progress of the work, viz., C. gigaspora, C. Cross- 

 landii, C. straminea and C. persimilis. In two cases only has 

 it been necessary by following the International Rules of 

 Nomenclature to change a name. C. muscoides Linn, becomes 

 C. corniculata Fr., and C. conchyliata Allen becomes C. Bizzo- 

 zeriana Sacc. One plant usually listed in British works as a 

 species, C. fastigiata, is reduced to the rank of a variety (C. 

 corniculata var. pratensis) and 22 names have been excluded 

 from the British list as synonyms or indeterminable. 



With regard to the citation of synonyms and illustrations 

 the list, though fairly full, does not profess to be completely 

 exhaustive. Well-known names have in all cases been cited, 

 but doubtful names have been omitted. Of illustrations, 

 those occurring in British works have been quoted, and a 

 selection has been made from other works, choosing those which 

 are well known and best represent the species in question. 



Before closing this introduction we would acknowledge our 

 indebtedness to all who have helped the work by forwarding 

 specimens. Many of the species are so rare in this country 

 that but for their aid there would have been little chance of 

 examining fresh material. As practically every working 

 member of the British Mycological Society has helped in this 

 way, it is impossible to mention each one individually. The 

 late Mr. G. Massee suggested the work and liberally handed 

 over a number of notes and drawings. Mr. Carleton Rea's 

 help was invaluable, and we are indebted to Mrs. Rea for the 

 loan of her matchless collection of paintings together with 

 notes. Amongst other members of the Society who have 



