PREFACE. ix 



enlargement, just as a miniature of the human visage is more agreeable 

 than one of colossal size. Besides, certain subjects become indefinite in 

 proportion to the magnifying powers ; where these are very high, unequal 

 surfaces cannot be brought within a common focus. In general, the lower 

 the power the better. 



All specimens ought to be healthy, vigorous, and entire. A portion 

 is seldom a satisfactory type for the whole. As the truth and accuracy of 

 observation depend greatly on the number and quality of specimens, one 

 only should not content the naturalist, nor should he dispense with many. 

 Delineation ought to be the inseparable companion of description. 



I have endeavoured to practice this rule throughout, from conviction 

 of its utility. 



Among many accomplished artists to whom this work is indebted, I 

 cannot omit the late Mr Peter Syme, an eminent flower painter, who last 

 superintended the academical department of his particular pursuits at 

 Dollar, — also the late Mr Alexander JMacaulay, an amateur who devoted 

 much of his time to similar studies, — Mr John Welch, an excellent minia- 

 ture painter, whose exquisite productions from the microscope are entitled 

 to the highest admiration, — likewise Mr Andrew Thom, presently occu- 

 pied in paintings for the Stained Glass Windows of the House of Lords, 

 whose accuracy and patient diligence exceed all commendation. 



It is not without diffidence that I venture to offer the following frag- 

 ments to the public, seeing that there are numbers of the scientific world 

 so much better qualified for the task My purpose is repeatedly explained, 

 as designing them to be viewed only as some detached Memoirs, com- 

 posed from an accumulation of facts. 



I profess no more than to speak of the living subjects I myself have 

 beheld, and such as belong to Scotland. I disclaim all pretensions to dis- 

 covery. I think, indeed, it would be difficult to name the first observer 

 of Nature's offspring, whose race has existed since the beginning of time. 

 If speaking personally of subjects occurring to me, it is by no means to 

 disparage other naturalists, to whom I shall always render the homage 

 due : if omitting quotation of the works of celebrity, it is from my inabi- 



