1866.] 



Dr. Davy on the Bursa Fabricii. 



99 



the bursa was nearly globular and about '7 by '6 incb ; it was distended, 

 as was also the cloaca, with a turbid fluid abounding in lithate of ammonia. 

 Its inner surface was not plicated, but slightly pitted. Of the others, the 

 bursa differed little from the last ; it was somewhat smaller. In the bursa 

 of one of these some flakes were found, consisting chiefly of lithate of 

 ammonia. 



XYIII. Carrion-crow (C. corone). — Of a young male shot on the 21st 

 of June the bursa was globular, very like that of the rook, about "7 inch 

 in diameter ; it contained some flakes of lithate of ammonia. 



Of another, shot on the 30th of June, weight 6163 grs., the bursa was 

 somewhat different in form; it was broadest at its base; it measured '9 

 by '8 inch. 



Of one killed on the 16th of July, weight 5653 grs., the bursa was 

 smaller ; it contained some flakes of lithate of ammonia. 



Of a fourth, killed in February, which, judging from the smallness of the 

 oviduct, was not an old bird, the bursa, had it not been for its opening 

 into the cloaca, might have escaped observation, not on account of its 

 smallness, for it was little less than that of the preceding, but from the ex- 

 treme thinness of its coats and adherence to the adjoining tissues. 



XIX. t7acM«z^ (C. monedula). — Three specimens have been examined. 

 Two of these were old ; in neither of them was there a bursa : one was 

 young ; it was shot on the 11th of July, and was fully fledged ; its bursa was 

 pretty large, similar to that of the rook, and empty. 



XX. Jai/ (C. glandarius). — Of one, judging from the state of its bones, 

 hatched in spring, the bursa was comparatively large, heart-shaped, mea- 

 suring '6 by '4 inch. Its cavity was small ; its inner surface smooth, 

 without plicae. 



XXI. Blackbird (Turdus merula). — Six difl^erent specimens have been 

 examined. In an old bird shot in March, a male, no trace of a bursa was 

 found. 



In an unfledged nestHng, weighing 112 grs., found dead, the bursa was 

 so thin as to be translucent ; it was proportionally large, and contained some 

 flakes of hthate of ammonia. 



In the others, which were examined between the middle of June and 

 the beginning of October, none of them, it was inferred, more than five 

 months old, the bursa, nearly globular, was from about '4 to "5 inch in 

 diameter ; its lining membrane was smooth ; its parietes proportionally 

 thick. In each instance it was empty. 



XXII. Song-thriish (T. musicus). — In an old male examined on the 

 28th of June no bursa was found. 



Of two young ones obtained on the 15th of the same month, the bursa 

 was about the size of a large pea ; one was empty, the other contained 

 some lithate of ammonia. 



XXIII. Water-ousel (T. cinclus). — In one, a male, probably a young 

 one, a small bursa was found. It was shot on the Uth of November. 



