L08 



NATURAL SCIENCE [August 1898 



question is, which ran bring forward the greater number of correlated 

 facts in support of these two deductions, respectively, i.e., so that they 

 may be supported by inductive evidence? Now gravity is claimed 

 as acting on one petal, but it cannot account for the erect stamens 

 and style in the dead-nettle, and all the rest of the features of the 

 flower. My suggestion is that the irregularity seen in all the organs 

 of the flower are brought about by one and the same cause, — the 

 mechanical action of the insects which visit it. 



Assuming the deduction as a working hypothesis, I bring forward 

 (1) abundant evidence to show that protoplasm responds to mechan- 

 ical forces and builds up structures to meet the strains to which it 

 is subjected ; (2) the ribs of the calyx and its form corresponds pre- 

 cisely with the distribution of forces, as seen in Salvias. The form 

 of the corolla is just what would result if it be supposed to be plastic 

 and moulded to the form of an insect, as in Anhatoda. The stamens 

 are erect or decimate, in correspondence with a flower having a 

 landing-place on the corolla or not. The honey-gland is situated,, 

 and the ' guides ' directing to it, precisely in adaptation to the insect 

 visitor. In fact, the entire flower is simply a vast accumulation of 

 innumerable coincidences, all conspiring to one and the same end. 

 It is this which constitutes inductive evidence : while all the correla- 

 tions are based on the well-known properties of protoplasm, the 

 accumulation of coincidences affords a probability of so high an 

 nriler as to amount to a 'moral conviction,' and such — all logicians- 

 admit — is equivalent to a ' demonstration.' 



Similarly, I maintain by inductive evidence that Monocotyledons- 

 have descended from aquatic Dicotyledons. 



These two lines of proof are amply sufficient, as scientific 

 evidences, to establish the truth of any theory, and convert it into- 

 a natural law. 



I think I have now said enough to show the utter incompetency 

 of a priori assumptions to prove anything at all, of themselves. They 

 are simply deductions, without verifications, and as such remain 

 utterly valueless, and instead of advancing any branch of science, 

 do but retard it, as long as they are accepted without verification. 

 Their danger, however, is subjective not objective. A deduction 

 or d. -priori assumption is useful only as the first step. It must be 

 verified. It is the fatal facility of guessing inherent in mere think- 

 in-, irrespective of facts — to collect which is a laborious process, in 

 which Darwin set so grand an example, and upon which evolution 

 was based. This is the imperishable result of his labour, while the 

 theory of Natural Selection, as having anything to do with the Origin 

 of Species, was a quite subordinate matter, and has turned out to be 

 a broken reed to rely upon. George Hexslow. 



De itton Bouse, Ealing, W. 



