93 m. INTRODUCED SPECIES. 



logical. His attempts at reasoning were often superficial 

 and unsound, and his arguments irrelevant. Even in 

 recording facts, and in matters of simi>le observation, his 

 statements were occasionally inconsistent and self-contra- 

 dictory. He was one of the authors by whom a foreigner 

 wovild be misled, if relying too imj)licitly on his writings ; 

 although a discerning English botanist may derive use- 

 ful hints and information therefrom. 



But Dr. Bromfield is not alone. Other English writers 

 have so described the situations of plants, as almost cer- 

 tainly to mislead, if their indications should be trusted as 

 given with perfect accuracy or with exhaustive complete- 

 ness. Some additional examples of this will not be si^ace 

 wasted, if they are received as suggestive hints for greater 

 exactness on the part of future writers. In the second 

 volume of this work Polygonum Persicaria is entered as 

 " agrestal, inundatal ; " and Polygomim lapathifolmm is 

 designated " agrestal, inundatal, &c." In Babington's 

 Manual of British Botany both species are located alike, 

 " in waste and damp places." Assuming these indications 

 to be correct, the two species are found in similar situa- 

 tions in Britain ; the second rather more varied in its 

 situations, perhaps, than the first. If we next turn to 

 the English Flora of Smith, — not a careless writer or a 

 despised work, — we shall find the situations of the two 

 species very difi'erently described. Polygonum Persicaria 

 is there stated to occur " in ditches, wet fields, and watery 

 places, common " ; and the Polygonum lapathifolium is 

 indicated "in cultivated ground, especially such as is rich 

 and moist, and on dung-hills." 



How would these diff'erences of indication influence the 

 foreign phyto-geographer, who should rely upon them as 

 tests of nativity or non-nativity of the two species in 

 Britain ? Looking to the Cybele or to the Manual, he 



