412 



GENERA AND SPECIES IN FUNGI. 



M. C. COOKE, LL.D., M.A., A.L.S., V.M.H. etc. 



{Contimied from page jg2). 



Not only does Polystictus ahietinus and also Porta vaporaria 

 sometimes assume the distinguishing features of Irpex, but also 

 other species of the Polyporei normally pass into Irpex, and 

 thus unite the Polyporacece with the HydnacecB. But if we quit 

 genera and the larger groups, and direct attention to species 

 themselves, the most indefatigable field hunters will be able to 

 furnish many instances which have come under their own 

 observation, in which allied species have exhibited so close an 

 affinity that it has been difficult to decide to which species the 

 abnormal forms actually belong. 



Let any one examine at a foray a hundred specimens of 

 Amanita phalloides and Amanita mappa, and I venture to 

 predict that they will be able to show a complete series of grada- 

 tions in which it would be impossible to determine where the 

 one species ends and the other begins. 



The larger the experience of the mycologist in field work 

 the more ready w^ill he be to acknowledge the many instances, 

 which have presented themselves in which abnormal forms 

 or ' missing links ' have presented themselves, in which it 

 seemed impossible to determine, with any certainty, to which of 

 the two species the delinquent actually belonged. And it is 

 these ' missing links ' which constitute the gradation of species 

 into species, and genus into genus, so as to combine and form 

 a graduated series, sliding and melting the one into the other, 

 and forming one continuous and harmonious whole. 



It would be absurd to suppose that any one who is 

 acquainted solely with a local flora could realize this transition, 

 or recognise more than a very few of the missing links,' but 

 the more his experience is expanded, the larger the number 

 of these ' abnormal ' species (as they have been called) will 

 have come under his notice. 



In the present notes I have confined myself almost entirely 

 to British examples, whilst a large number of exotic examples 

 have constantly floated through my memory- to strengthen 

 me in my hypothesis. 



I find myself strengthened in this belief collaterally by re- 

 membering that Worthington G. Smith, some quarter of a 

 century ago, advocated a view which would be practically 



