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often carried on anlidst a constant fight for " a^propriatio;ns,"!an4 

 a liability to upset from the exigencies' of the; political situation, 

 — trials happily unknown to our raorie favoured -scientists.. r : . 

 It had often been remarked, and Miss Crane thoujifht with 

 truth, that the doctrine of evolution was more readily accepted iti 

 America than in Europe. The seed fell on good ground in t'hs 

 western world, for the minds of scientific i workers in general 

 seemed more favourable to its acceptance as a working principle 

 in biological investigations. They sought more to prove the 

 argument thai; to controvert it. They were, perhaps, less blinded 

 by that third eyelid, the nictitating membrane, which that genial 

 and witty philosopher, Wendell Holmes, declared to be commo'n 

 alike to reptiles, some birds, and theological students, and, by 

 paeans of which he drily said, " they shut out not all the light — 

 but all the light they do not want." The genus is not absolutely 

 unknown on this side, although more rare than formerly ! We 

 9.11 retain the vestiges of this membrane in our physical structure. 

 It is now more than thirty years since Darwin first addressed a 

 letter to Thomas Davidson, suggesting that no one could work 

 out the question of the Evolution of the Brachiopoda better than 

 he. The letter will be found on pp. 366 and 367 of that most 

 interesting record, " The Life and Letters of Charles Darwin," 

 edited by his son, Francis Darwin. Davidson felt compelled to 

 answer the question with a direct negative in his classical memoir 

 on " What is a Brachiopod ?" first delivered before the Brighton 

 and Sussex Natural History Society, on February 11th, 1876, and 

 subsequently published in French in the annals of the Malaco- 

 logical Society of Belgium, and two years later in The Geological 

 Magazine. In the summary of his great work on the British 

 Fossil Brachiopoda, published in the volume of the Palaeonto- 

 graphical Society for 1884, he did not modify his original opinion, 

 stating that " he still found the subject of the descent with 

 modification among the Brachiopoda beset with so many 

 apparently inexplicable difficulties that year after year has passed 

 away without my being able to trace in a satisfactory manner the 

 descent with modification among the Brachiopoda which the 

 Darwinian theory requires." He appears at most to have 

 admitted a kind of dual control ; species sometimes modified 

 themselves, genera originated in a different manner. But, really, 

 the supervision of generic creation and extinction among the 

 Brachiopoda would have been no sinecure. The subject (proceeded 

 Miss Crane) was frequently discussed between us, but we never 

 agreed upon it, for, being ultimately convinced of the general 



