114 MEETINGS. 



and about a dozen of the latter on Whit-Monday at 

 L'Ancresse. 



Supplementing Mr. Philip Nicolle's paper read at the 

 previous meeting, Mr. A. Collenette now contributed a 

 short and concise, but very suggestive paper on " The Cuckoo, 

 as illustrating the processes of Natural Selection." In this 

 he held that cuckoos originally had ordinary bird habits, 

 flew in pairs, nested on the ground, and brought up 

 more than one nestling. The first cause of a change was 

 probably scarcity of food which, in the presence of some 

 conditions, would have tended to lengthen the interval 

 between the laying of the eggs, and to have developed the 

 nestling's habit of throwing out of the nest the second or 

 other nestlings. The habit of the young bird has been 

 acquired under stringent conditions, for its bony structure 

 and infantile peculiarities result from a long struggle for 

 existence, during which only those birds which were able to 

 overcome other nestlings newly hatched would survive. 

 The character of the food gives the same indications. The 

 cuckoo eats hairy caterpillars. No doubt it took to them 

 when other kinds were scarce, and at last grew to prefer them. 

 The cuckoo lays its egg on the ground, but usually lifts the 

 egg in its mouth and carries it to a convenient nest. This 

 points to the same scarcity of food as the prevailing cause 

 of the change of habits ; if not satisfied with the place where 

 the egg was laid, it had to fly in search of a good feeding- 

 ground before hatching it out. This in its turn led to choice 

 of nests of birds which were feeding on the same ground, and 

 to a strengthening of the nestling's habits. Natural selection 

 would then act powerfully in developing the present peculiari- 

 ties of the bird, which would adhere to those nests by preference, 

 which had formed its habits ; thus different birds would 

 produce different eggs in consequence of the gradual selection 

 of eggs near in colour and size to those of the chosen foster 

 parent. The supposition is, therefore, that colour and size of 

 eggs, as well as the nest chosen, has descended from generation 

 to generation on the side of the mother. This is strengthened 

 by observation, it being believed that the same bird lays in 

 succession the same variety of egg and uses the same nest. 

 The natural result of the selection going on will be that in 

 time the variations will accumulate in several branching lines, 

 and will produce a number of distinct species. 



The discussion which followed the reading of the paper 

 was of great interest, and teemed with anecdotes about the 

 bird and its habits, some of which were valuable because of 



