538 THE OANNET 



sufficiently to be so used. With his assistance the brain 

 of an adult Gannet was carefully extracted from a head 

 sent by me to the Cambridge Physiological Laboratory, 

 and found to weigh 19,4 gramms. In proportion to the 

 weight of the body this must be Ioav as compared with 

 the brains of the Corvidce, and many other birds. As 

 already stated, the cavity in a Gannet's skull is not large, 

 and in some respects the Gannet appears to be rather 

 lacking in intelligence ; yet it is difficult to measure the 

 intelligence of any animal by a human standard. 



The Ears. — The ears of a Gannet are remarkably small, 

 and closely covered with feathers — another provision to 

 keep the water out. The orifice, which is nearly round, 

 measures externally .09, but the passage increases in width 

 as it goes further in. Small as the orifice is, a Gannet 

 can still further contract it, as I have observed when 

 holding a Uve one, and this power of contraction is most 

 likely exercised in the act of plunging.* 



The Oil-gland. — The oil-gland or uropygium, situated 

 on the lower part of the back, is thickly covered with 

 feathers, and very flat. It consists of two glandular 

 receptacles, united in one, but presenting distinct orifices, 

 and Mr. Ticehurst considers it of the largest proportional 



* The ear of a Cormorant is equally small. 



