290 DISEASES OF DOMESTICATED BIRDS 
the nervous centers. A proof of that influence is seen in the phenom- 
ena of somnolence which dominate the morbid scene, in the hyper- 
esthesia which is manifested by the transitory crises and last by the 
interference with locomotion.. 
The lesions are chiefly in the digestive canal. The buccal mucosa 
is covered with a yellowish brown layer which is viscid and adherent. 
When this is removed, marked congestion is seen, with hemorrhages 
at some points. The mucosa of the crop shows traces of a violent 
irritation with numerous hemorrhages and superficial ulceration. 
The mucosa of the esophagus shows general congestion with super- 
ficial erosions. The intestinal mucosa is hyperemic, hemorrhagic 
and ulcerated. The principal visceral organs such as liver, spleen, 
kidneys, lungs, heart and nervous centers such as brain and cord 
show more or less marked congestive lesions. The blood possesses 
a characteristic bright red color. 
Edwards found that doses of salt as high as 2.5 grams per kilo- 
gram of body weight administered to pigeons by injecting into the 
crop, produced no effect. A dose of 4.5 grams per kilogram of body 
weight caused great depression, followed by death in eighteen hours. 
A similar dose of 3.33 grams per kilogram caused death in twenty- 
three hours. No lesions other than acute congestion of the mucous 
membrane of the lower portion of the esophagus were observed. 
Only about 25 pey cent of the salt was absorbed from the crop. 
SODIUM NITRATE 
Lethal dose. 2% drams. 
Toxic dose. 1% drams. 
Non-toxic dose. %% dram. 
Experiments. (1) February 20, 9.50 a.m. Gave fowl 2% 
drams of sodium nitrate. 11 a.m. Fowl dull and droopy. 12 m. 
Fowl shows increased dullness, droopiness and sleepiness. Sitting. 
lv.m. Fowl is wide awake but dull. Is ina sitting posture. Legs 
paralyzed, cannot stand. 3 p.m. Fowl lying on its side, cannot 
move, legs paralyzed. Greatly depressed. Death appears imminent. 
4.30 p.m. No change from above. February 21, 9 a.m. Fowl 
died during night. Autopsy notes. Crop wall and skin covering it 
dehydrated. These membranes were transparent, dry and tough. 
Proventriculus shows marked catarrhal exudate. Inner membrane 
of gizzard separated from submucosa. Considerable fluid beneath 
inner membrane. Catarrhal enteritis. Duodenal mucosa congested 
