140 



atum and sagittatum. It is clear therefore that the study 

 of varieties is not so exclusively modern as some of us 

 have been apt to suppose. 



Leaving the herbarium the next step was to see if possible 

 the plumosum from which Howlett raised his kalothrix. 

 Unfortunately no record could be found of this nor could 

 any information be had about Mr. Howlett himself. 

 There was, however, only one form of plumosum in the 

 gardens (labelled simply A. f.f. plumosum). This was 

 not the Horsfall plumosum, but was unmistakably the 

 plumosum which comes from the spores of kalothrix and 

 from which kalothrix can in turn be raised. It has some 

 resemblance to the Horsfall form, but is a dwarfer plant, 

 thinner in texture, less acute in the ultimate segments, and 

 when exposed to the sun, as it was here, it burns to a 

 peaty brown which is very characteristic and unmistak- 

 able. If this be, as seems probable, Ihe plumosum from 

 which Howlett raised his kalothrix it is at least equally 

 probable that it was itself the offspring, immediate or 

 remote, of another kalothrix. And if so of what kalothrix ? 

 Sherard's plant is the only one known to have existed 

 previously. Everything, in fact, points to the Mourne 

 Mountains plant as the ancestor of the modern kalothrix. 

 It is clear, from the number of varieties in the herbarium, 

 that Sherard was a student and admirer of these things. 

 It is therefore extremely unlikely that, upon finding so 

 good a thing as kalothrix, he would leave it behind in the 

 Mourne Alountains and content himself with a dried frond. 

 If he were the man I take him to have been he would 

 transfer the whole plant alive to his vasculum and after- 

 wards cultivate it carefully in his garden. 



The comment of Ray, quoted above, is indirect evidence 

 that kalothrix persisted as a living plant, for what would 

 be the use of giving a new name to a fern of which only 

 a dried frond was known to exist ? Suppose now the fern 

 to be growing in some snug sheltered place in Sherard's 

 garden. We have seen that he left money to the University 



