Moss: Changes in the Halifax Flora. 



169 



were abundant in the stations named before they received the 

 attentions of these tradesmen. I am also credibly informed that 

 a certain local landowner is responsible for the disappearance of 

 the Snowdrop from many fields in the Luddenden Valley. The 

 ' pilgrimages ' which some local naturalists' societies annually 

 make to the haunts of Trientalis, Pyrola, Andromeda, Paris, 

 and other local rarities are highly reprehensible ; and they have, 

 to my personal knowledge, been responsible for the great 

 diminution in numbers of many of these plants. 



IV. This is an interesting class, and includes those plants 

 which were, so far as one can judge, rare in Bolton's time, and 

 which are in pretty much the same condition to-day as they were 

 in his time. 



The plants of the narrow, western cloughs represent those 

 which have changed the least, as villages are rare in them 

 owing to difficulties of transport. Mills, too, are scarce 

 amongst them, hence the rapid clough streams are not con- 

 taminated with much sewage or mill-refuse. Moreover, these 

 cloughs, by their great depth and narrowness, are somewhat 

 sheltered from the smoke of the towns. Where clough plants 

 have disappeared it is almost always owing to the draining of 

 those portions which abut on the moors, or to the depredations 

 of trippers in places like Hardcastle Crags. 



Considerations of this nature support what I early stated, 

 that Bolton made an error in recording CEnanthe fistulosa for 

 the cloughs throughout the parish. CE. crocata is the plant 

 there now; and if we assume that this was the plant intended, 

 the record is in keeping with the general conclusion arrived at, 

 viz., that the plants in the cloughs in 1775 are the same as those 

 in the same places to-day. If Mr. Lees* wishes us to believe 

 that CE. crocata has displaced CE. fistulosa he must show how it 

 is possible that the causes effecting such a remarkable sub- 

 stitution of one species for another have not affected other 

 plants in the same areas. The following species may be taken 

 as typical of the clough plants recorded by Bolton which have 

 maintained their respective habitats: — '5 Pinguecula vulgaris/ 

 '7 Iris Pseudacorus 32 CEnanthe crocata, sub nomine 

 ' CEnanthe fistulosa,' '61 Stella ria ncniorumf 'c)^ Troliius 

 Europceus,' k 120 Cardamine amara," * 14c) Carduus tuicuoides ' ' = 

 C/t. heterophyllus Willd., '167 Orchis bi folia' Habenaria 

 bi folia R.Br, and ' 1S1 Salix rosmarini folia ' — S. refens Linn. 



ic)oo June i. 



The Naturalist,' February 1900. 



