538 General Notes. 
the so-called “dust” shot was used in shooting the specimens, 
which, as soon as they were killed, were placed in a cool place, and 
weighed within a few hours afterwards. It takes twelve of these 
dust shot, by actual count, to equal a grain weight, and advantage 
of this fact was taken into account in estimating the weight of the 
shot that passed through the skin of the specimens, and subse- 
quently deducting this after the weights of the individual had been 
taken. This was obviously of little importance in the ultimate 
result; however, every precaution was taken to avoid errors. The 
weight of the brain and body are given separately, and the relative 
weight of the former to the latter, all the weights being designated 
in grains, as a matter of simplicity. In the weighing of the speci- 
mens the bird with all its parts intact was laid upon the scale-pan 
of a prescription scale similar to those used in apothecary stores, 
which weigh accurately to half of a grain. After being weighed 
and noted, the brain of the specimen was carefully removed + by 
making a circular incision, and the removal of the piece of bone, 
thereby cut free, from the posterior part of the cranium by means 
of a small scalpel. The opening that remains after the operation 
being sufficiently large to admit of the withdrawal of the entire 
encephalon after the optic nerves have been severed and the spinal 
cord likewise treated below the medulla oblongata. After the brain 
was removed in this way it was weighed upon a more delicate sad- 
dle-back scale, which weighed accurately as low as the tenth of a 
grain. Forty-seven birds were thus weighed, and for purpose 0 
comparison with some small mammals four adult specimens of the 
common house mouse, Mus musculus, and one specimen of 
common gopher, Spermophilus tredecimlineatus, are reckoned. 
5 > i Op 
Weight | Weight Bee gee 
Name of Specimen. of of |Sex. ZEA 4 2g 
Body. | Brain. | gos ges 
da 
Turdus aliciæ 5894 | 12 Q; 1-49 May 20th 
Turdus ustulatus swainsonii...... | 445 124 1-36 i115th 
Turdus aonalaschkæ pallasii... | 430 | 123 [ee ce Aprill 
ae ee as gma 20 133 a aes “ 
Galeoscoptes carolinensis.......... 546 14; 1-37 |June 4th 
Harporhynchus rufus 1158} | 264 1-44 < 
be Se aha i 1170 264 -44 is 5th 
Regulus calendula 924 54 6 J pe Oct. i 
Regulus satrapa 974 GB, taia 1- K 
arus atricapillus 1764 104 8 1-17 Feb. 26th 
s a 1593 | 9 LA n aa 
by the regular method that is employed in the skinning of bird 
1 This did not necessitate any injury to the skin, as it was apn 
entific study. 
