I op 



Moss : Changes in the Halifax Flora, 



Watson's History of Halifax being 1 Bolton's, is the number of 

 inaccuracies it contains. Rut even apart from this it cannot 

 yet be said that the Boltonian authorship is established beyond 

 question [9]. Mr. Crossland | 14I writing in February last, says 

 of this list that it is ' supposed to be J. Bolton's.' 



Now the changes which were found to have taken place in 

 the parish of Halifax during the time specified were practically 

 all due to man's interference w ith Nature ; though it was 

 nowhere stated or implied that, if the survey were extended 

 over a much longer period of time, many natural changes would 

 not be revealed, as such a fact w as regarded as obvious. Hence 

 it is not to the point to reply that our moors were prehistorically 

 tree-clad, to quote evidence from late glacial deposits, and to 

 gather examples from all quarters of the British Isles except 

 the particular area to which my conclusions were definitely 

 stated to apply ; although all these points are without doubt 

 highly interesting and important in their way. Neither was one 

 much concerned with intra-parochial changes, such as occur 

 when a small garden is enclosed, but chiefly with those changes 

 which had occurred in the parish of Halifax as a whole, with 

 regard to the extinction, the persistence, and the introduction of 

 species. It seemed to me — and the discussion has confirmed 

 me in this opinion — that if such work were done in many areas, 

 some general conclusions would be deducible, which would tend 

 to minimise the vague and unverified ideas which at the present 

 time obtain in the minds of field botanists regarding' floristic 

 changes ; and I greatly regret that the original and simple issue 

 should have been so beclouded as to render necessary its 

 re-statement. 



The question of the possible substitution of (Knanthe fistulosa 

 bv CE. crocata was very carefully considered, as in Halifax there 

 was a case parallel, in all essential points, with the Adel 

 one [7]. Reasons were given for believing that Bolton erred in 

 his record of CE. fistulosa, and that the plant in the Halifax 

 cloughs then, as now, was CE. crocata; and this position was, if 

 only for a moment, admitted in the 'Rejoinder' [9] to be 

 'probably right.' Although in June a list of aquatic plants was 

 given, the introduction into Halifax of which was put down to 

 man and his works, yet it was felt that CE. crocata could not be 

 rightlv placed in such a category. For all those recently intro- 

 duced aquatics were noted to be such as inhabited stagnant or 

 slowly moving waters, which in Halifax are only found in the 

 canals and mill dams at the lower levels of the parish, while the 



Naturalist. 



