Suter. — The Origin of a New Species by Isolation. 283 



specimens, but foimd only dead shells, and he considers the species to be 

 now extinct. That a species laying only one egg would not increase in 

 number is evident, yet Lesson and Martinet say that in the last century 

 these snails were abundant on the Great King. I cannot find any record 

 that there are rats on the island. These, of course, would dispose of some 

 snails. Then we have to remember that Maoris were at one time living 

 on the Great King, and they may have eaten a good number of these snails, 

 but I am unable to say whether Maoris ever used Placostylus as an article 

 of food. Remembering the terrible wreck of the " Elingamite " at 10 a.m. 

 on the 9th November, 1902, and that a party of those saved had to live 

 without food for several days on this island, I think it is possible that some 

 person or persons may have discovered these snails and eaten all those they 

 found. It would gladden my heart if I knew this had been the case. 



The most interesting question, however, is, How did the snails know 

 that they produced too many eggs ? How did they perceive that laying 

 fewer eggs, increasing most likely their size, and finally sticking to one egg 

 only, would be their salvation ? We are only too ready to underestimate 

 the mental faculties of the lower animals, and there is no likelihood that we 

 shall ever get an approximately correct knowledge of what is going on in 

 their small brains. We cannot deny that they possess mind, which means 

 will and intelligence, and may be described as accumulated consciousness 

 and accumulated faculty. And a still more interesting fact is that thou- 

 sands and thousands of years back the Placostylus on the Great King 

 practised Malthus's " principle of population." There is nothing new 

 under the sun. 



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