54 Mr. W. Evans on the Periods 



The results of these experiments and observations will be 

 found in the second,, third, and fourth columns of the annexed 

 Table. Column 4, showing under each species the number 

 of eggs hatched, has been added so that, should the results be 

 combined or compared with those of other observations, 

 they may have no more than their proper weight assigned 

 to them. 



The number of species included in this part of the Table 

 is seventy-five. Eggs of the Bearded Tit, Swift, Greeu 

 Woodpecker, Kingfisher, Tawny Owl, Sparrow-Hawk, Ptar- 

 migan, Water Rail, Redshank, Great Crested Grebe, and a 

 few others were also tried, but without success. I should 

 mention, however, that in each of these cases the expei'iment 

 depended on a single egg, and that all of them had been 

 transmitted by parcel-post from a distance, the rough hand- 

 ling thus encountered having, doubtless, at the outset de- 

 stroyed the vitality of the greater number, if not, indeed, of 

 all of them. To ensure success the eggs should be gathered 

 as near home, carried with as little motion, and placed in the 

 incubator with as little delay as possible. If they must travel 

 a distance they cannot be too carefully packed. An excellent 

 plan is to roll each egg in the centre of a thick ball of dry 

 moss, and then pack them securely, in an upright position*, 

 in a box of ample -size. Above all avoid the use of a hammer 

 in fixing the lid. Six eggs of the Red-legged Partridge, 

 packed in this fashion, and kindly sent by Lord Walsinghara, 

 all produced healthy chicks. The thick-shelled eggs of the 

 gallinaceous birds appear, however, as a rule, to withstand 

 the injurious effects of transit better than any others. 



Differences of opinion doubtless exist as to how far results 

 obtained by artificial means can be relied on as exponents of 

 the duration of incubation under natural and normal con- 

 ditions. For my own part, I have no hesitation in accepting 

 them as substantially correct. No doubt individual cases 

 may differ somewhat from the natural average, but not more 

 so, I think, than is frequently the case among eggs naturally 

 hatched. The extent to which development may be ac- 



* Wright, in his * Book of Poultry ' (p. 42), strongly recommends the 

 packing of the eggs with the large end down. 



