VOl l909^^ I ] Townsend, Use of Wings and Feet by Diving Birds. 239 



they are used under water much in the same manner as during 

 flight." 



The plunge of the Gannet, with wings partly open, is so swift 

 and often from so great a height, that it seems probable that there 

 is no need of either wings or feet under water, but that the initial 

 impulse of the plunge, which must be greater than that of gravity 

 alone, is sufficient to enable the bird to catch its prey. 



Cormorants execute graceful curves in diving with wings close 

 pressed to the sides, often throwing themselves clear of the water 

 with their powerful feet. I have never seen them under water 

 but have conclusive evidence from literature on this point. F. W. 

 Headley (6) says: "The Cormorant uses his feet alone to propel 

 him [in diving] striking with both simultaneously, and holding his 

 wings motionless, though slightly lifted from the body. The 

 position of the wings must have given rise to the idea, common 

 among fishermen, that the Cormorant flies under water.... But 

 when you see him in a tank you can have no doubt that the legs are 

 the propellers." Mr. Beebe, in a letter, confirms this observation 

 from his experience with Cormorants in tanks. Selous (23), 

 speaking of Shags, both adults and full grown young, observed in 

 caverns in the Shetland Islands says: "Others, whose young were 

 still with them on the nest, although full-fledged and almost as big 



as themselves, plunged, attended by these into the water It was 



easy to follow these birds as they swam midway between the sur- 

 face of the water and the white pebbled floor of the cavern, and I 

 was thus able to confirm my previous conviction that the feet alone 

 are used by them in swimming, without any help from the wings, 

 which are kept all the while closed. I have many times observed 

 this before, but never so clearly or for such a length of time." 

 Lea (11) says of Shags: "This species also may be watched at the 

 'Zoo'. It always begins its dive by jumping up in the water and 

 taking a header, and then strikes hard upwards with both feet. 

 You will see that it does not use its wings at all for swimming, but 

 holds them quite still, lifted just a little away from its body. It 

 strikes out with both feet simultaneously, and in this differs from 

 the Darters (Plotus), which adopt an alternate stroke, as you may 

 see for yourself by visiting the Diving-birds' House at feeding- 

 time." In this connection it is interesting to note that Cormorants 



