ANIMAL HEAT. 115 



already quoted, since he tells us that he wit- 

 nessed the hatching of the eggs of a species at 

 Gongo Soco (a mountain district) in a shallow 

 unfinished nest, a heavy rain pouring down for 

 several days and nights, while the mother was 

 sitting. "We believe that the temperature re- 

 quired for the development of the chick in the 

 egg will be found to differ in a few degrees only 

 among all birds which incubate (some in Aus- 

 tralia do not incubate, but put their eggs into 

 hotbeds of their own making). Why, then, 

 should we suppose that the quantity of animal 

 heat given off from the body of the Humming-bird 

 is not sufficient for two eggs, seeing that in our 

 country the Tits will hatch many eggs, some 

 species ten, twelve, or more ? The Kingfisher in 

 its dark damp hole hatches six or seven. The body 

 of the Longtailed Titmouse (Parus caudatus) is 

 not so large in proportion to the number of its 

 (ten or twelve) as is that of the Humming- 

 |bird to its dual number. 



The nests of the Humming-birds are deep, if 

 >t domed, but in some species they are domed; 

 :, whether domed or not, the end aimed at, 

 ictively, by their thickness, softness, felted 

 3ter, and the materials employed, is the 

 jvention of the influence of active electricity 

 the eggs, which would immediately destroy 

 germ. And here we must quote a letter of 

 interest, from E. Hill, Esq, to the Zoo- 

 jical Society of London, dated Spanish Town, 



