476 DR. J. MURIE ON THE GULAR POUCH OF OTIS. [JunC 25, 



seeds, grass, or leaves being found in it appears to me only an acci- 

 dental circumstance, the absence of great muscularity in the walls 

 permitting the foreign body temporarily to he there. In this re- 

 spect I also agree with Nauinann* and Yarrellf, although I hardly 

 think that the latter naturalist was right in stating " such foreign 

 substances would destroy the bird by inflammation." 



3. What Cullen and other earlier authors (Schneider and Deg- 

 landt, for example) have said regarding the presence of the gular 

 pouch during the breeding-season in Otis tarda, and what has been 

 observed in the AustraHan Bustard in our Gardens, show that the 

 pouch is a feature connected with the reproductive function, and 

 only a temporary air-chamber. 



The gaudy Peacock swells out with tremulous emotion ; the Turkey 

 Cock, the Tragopan, and other birds erect their wattles ; the Pouter 

 Pigeon no less shows sexual phenomena akin, though in some re- 

 spects differing from that of the Bustards. 



4. From the statements of various observers, then, it would thus 

 appear that at least five species of Bustard occasionally possess a 

 gular pouch, namely Otis tarda, O. kori, O. australis, O. nigriceps, 

 and O. tetrax ; but others yet unexamined may also have it ; so 

 probably it obtains in the family Otidce. 



a. In a moderate-aged male Burchell's Bustard, as we have seen, 

 the pouch is very limited in dimensions. In young birds of this 

 and other species it has never been found ; and where its existence 

 has distinctly been proved, it invariably (with one apocryphal ex- 

 ception) has occurred in fully grown males. From these data I 

 think it may be inferred that the said " gular pouch" is an organ of 

 adult growth possessed alone by the male, and not attaining its full 

 dimensions until the bird has arrived at maturity. To such cir- 

 cumstances the incidental non-development of the organ may be 

 ascribed. 



6. There still remains the unexplained peculiarity that some adult, 

 and possibly it may be old, males have it not. This I confess is not 

 at all clear to me. If the organ is reciprocal with the procreative 

 faculty, enlarged or subject to an accession of growth during the in- 

 stinctive sexual season, then I cannot conceive why traces of the 

 pouch, and especially its opening, do not at all times exist — that 

 is, as soon as the bird has arrived at maturity. That the sac is not 

 the result of a bursting and exjiansion of the cellular tissue of the 

 throat, as Mr. Bartlett has suggested, I am perfectly satisfied of. 

 In emphysematous disease of the lungs in the higher Mammalia 

 rupture of the pulmonary cells and enlargement into a sacculus does 

 peradventure take place ; but in the cellular tissue of the neck of 

 birds we have tissues differently constructed. Moreover the same 

 objection applies in either instance ; for in the lung, as would be in 

 the Bustard's neck, such a lesion could not be inflated and com- 



* Oj). cit., and Ibis, 1862, p. 115. 

 t L. c. p. 118. 



I See Newton's paper, /. c. pp. 107, 115, quotations being there given from 

 the authors; the original volumes it has not been my fortune to consult. 



