522 THE GANNET 



Not the least remarkable fact connected with the air- 

 cells of the Gannet is the presence in them of a Mite or 

 Acarid, but of this more hereafter. 



To describe a Gannet's subcutaneous air cavities cor- 

 rectly, appears to be a very difficult task. Even so great 

 an anatomist as Nitzsch found it hard, and a plan which 

 I tried to make of the cells had to be given up as 

 hopeless.* One vacuity is five inches in length, according 

 to Professor Macgillivray, and another five inches and a 

 half, while a third of large size is stated by him to cover 



1774). An alphabetical list of many treatises is given by Mr. Mliller, but 

 here it is only necessary to mention those which refer to the Gannet : — 



G. Montagu, "Memoirs of The Wernerian Nat. Hist. Soc. " (1811), 

 pp. 176-190. 



G. Montagu, " Ornithological Dictionary," Supplement. 



R. Owen, " Proc. Zoological Society " (1830-1), p. 90. 



W. Macgillivray, " Audubon's Ornithological Biography," IV., 

 p. 237. 



W. Macgillivray, " British Birds" (1852), V., p. 419. 

 (In part reprinted from Audubon. ) 



C. L. Nitzsch, " Pterylography " (1840), English Translation, p. 150. 



H. Boulart, "Journal d'Anatomie et Physiologic" (1882), XVIII., 



p. 4G7. 

 Mile. F. Bignon, " Comptes Rendus de la Societe de Biologic," Paris 



(1889), p. 90. 



E. Deslongchamps, " Mem. Soc. Normandie, " Ser. 2, Vol. VIII. 



* Experiments to inflate the Cells with Gelatine. — With the assistance 

 of the late Professor Newton an attempt was made at Cambridge to 

 secure an impression of some of the air-cells in a pair of Gannets 

 (sent from the Bass Rock), by the injection of plaster- of -paris and 

 gelatine. It however proved a task of greater delicacy than had 

 been expected, the smaller tissues at once giving way under pressure, 



