Hatching Hawk’s Eggs. 
Friend Wade : Agreeable to yonr re- 
quest, I send you my experience in batch- 
ing eggs of our Rapacia. The result has 
not been very satisfactory thus far, but 
enough so to satisfy me that some of our 
Oologists who are very positive in their 
statements are mistaken (18 to 22 days). 
Mr. R. M. Jerome, of Plum Island, who 
has watched the nests of the Fish Hawk 
for years, says the period of incubation of 
this bird is about twenty-eight days. (See 
Familiar Science for June, 1880). From 
my observations I am satisfied that this is 
the time occupied by all our Hawks. In 
my articles published in Familiar Science, 
I stated that I believed twenty-one days 
was the period of incubation of all our 
diurnal birds of prey. This statement I 
made on the assertions of my collectors. 
May 2d, 1879, 1 put two Red-sho uldered 
Hawk’ s eggs under a hen May 29th, I 
took the eggs and broke them, expecting 
to find dead birds, as it was several days 
past the time of incubation given by any 
of our Oologists (27 days), but judge of 
my surprise on finding two lively Hawks, 
evidently just ready to hatch. 
In 1880, through the kindness of “ J. M. 
W,” I received eggs of the Barred Owl, 
: Cooper’s and Red-shouldered Hawk. The 
Barred Owl’s eggs were so thin-shelled 
that they were broken before two weeks 
had expired. On the 26th day the hen 
accidentally got shut out from her nest, 
and I did not find it out until the eggs 
were cold. On breaking them, two well 
developed chicks of the Cooper’s Hawk — - 
were found dead. The Red-shouldered d 
egg was addled. The past season, through C? 
the politeness of W. W. Coe, I received S3 
four eggs of the Marsh Hawk and one of ^ 
the Red-sliouldered. On the 30th day I * 
examined the eggs and found two chicks . 
of the Marsh Hawk had cracked the shell, £ 
but had been unable to extricate them- * 
selves. The other eggs were addled. ^ 
From the above I am satisfied that the q 
period of incubation of our Hawks is from 
twenty-eight to thirty days. I have made 
arrangements the coming season to test the 
matter with an incubator. If those inter- 
ested in this subject w'ill send me fresh 
eggs of our Rapacia, I hope to be able to 
settle positively this question. — William, 
Wood, East Windsor Hill, Conn. 
