THE ALBATROSS. 375 



foramina, probably for the passage of iiutritient 

 vessels to the substance of the gland. This 

 gland is found in most, if not in all, the aquatic 

 birds, but varies in them, both with respect to 

 exact situation or extent. On the dissection of 

 the common duck, I found it, not imbedded in 

 a bony cavity, but situated on a dense fascia, 

 slightly projecting over the superior and pos- 

 terior margins of the orbit. It is similarly situ- 

 ated in the boobies and others. In the Cape 

 petrel {Procellaina Capensis) this gland is situ- 

 ated partly in a narrow semilunar depression 

 over the orbit, and partly on a dense membrane, 

 continuous from the margin of this bony cavity, 

 extending from two orbital processes, serving to 

 complete the superior part of the orbit on which 

 the gland rested. A dense fascia covers the 

 glands, which fascia is not continuous over the 

 other part of the head, but binds the glands 

 firmly down in their situation. 



In the gull tribe {Lamis) it is situated in a 

 bony depression over the orbit, but more super- 

 ficial than in the Albatross, and extends over the 

 cranium, so as nearly, if not actually, to touch 

 the gland on the opposite side, and both ex- 

 tending so as to cover the anterior part of the 

 cranium. 



It is difficult to conjecture the use of this 



