BRAINS AND SPINAL CORDS IN ATAXIC PIGEONS 115 



No. K172. Young of cage 269a. Third generation on one side; 

 second generation on other. Side of third generation is through a 

 normal brother of no. K131, described above. Side of second genera- 

 tion is through ataxic female no. B661, which is offspring of original 

 ataxic female no. 151 mated to pure wild rock pigeon male C-B9. 

 From egg of 5/19/17. Ataxic — tips backwards. 



No. K158. Young of cage 130. Second generation from two normal 

 young of the two last-named birds: ataxic 151 and normal C-B9. From 

 egg of 6/17/17. Ataxic— tips or nods Ii3ad sidewise; tips backward, 

 and sometimes flies sidewise. 



No. K207. Young of cage 123aa. Second generation, from two 

 normals, male B533 and female B548; these latter were offspring of 

 original ataxic female 151 and scraggly male A 126. From egg of 

 6/22/17. Ataxic — somersaults backward, occasionally falling side- 

 wise; twists neck and head; does not fly; no coordination in any move- 

 ments observed. 



No. K167. Normal, is of same fraternity as K137. From egg of 

 6/19/17. 



No. K199. Normal, is of same fraternity as K207. From egg of 

 6/9/17. 



No. B473. Normal, older bird, is of same fraternity as K158. 

 From egg of 12/21/16. 



With the above detailed records we received the four ataxic 

 and three normal birds in good condition on October 26, 1917. 

 We observed them for more than three months, during which 

 time all of the four ataxic pigeons slowly became worse, while 

 the three normal ones seemed quite healthy and in good condi- 

 tion, living a very active life. 



The affected birds apparently are backward in their develop- 

 ment, they look smaller, their feathers are scanty; they have lost 

 the characteristic brilliant color, and appear lusterless. The 

 muscles are flabby. The birds maintain one position quietly 

 almost constantly. To support the body they stretch their 

 legs wide apart and a little forward with the tail braced against 

 the bottom of the cage and the trunk partly lowered to the floor, 

 so as to avoid falling forward, backward or to the side. The 

 pigeons, then, maintain their position while standing with three 

 supports just like a three-legged stool; two widely spread legs 

 and a tail braced against the floor. The affected birds do not 

 stand on the limb of a tree as normal pigeons usually like to do, 

 but remain on the floor of the cage, often supporting themselves 



