BIRD-NOTES 73 



fish, which it captures by diving into the water and 

 bayoneting them with its long sharp beak. The edges 

 of the mandibles are finely serrated, so that the 

 struggling fish, after it has been freed from the 

 "spear-point," can be securely held. The head is very 

 small, not exceeding in circumference the thinnest 

 part of the neck, which tapers from the base. The 

 "kink" in the neck is due to a peculiar arrangement 

 of the vertebrae ; the eighth vertebra is articulated at 

 right angles with the seventh and almost at right 

 angles with the ninth. Powerful muscles pulling on 

 the vertebrae can temporarily increase or decrease the 

 angles at which this eighth vertebra is set in relation 

 to those in front of and behind it, and as the Darter 

 swims through the water in pursuit of a fish, the head 

 and neck are constantly being jerked backwards and 

 forwards, in a manner which has aptly been compared 

 to the action of a man poising a spear preparatory 

 to hurling it. When the Darter is sufficiently close to 

 its prey, the head is driven forwards with great rapidity 

 and the fish is impaled on the beak. The large 

 webbed feet enable the Darter to rush through the 

 water at a high rate of speed, and as the entire 

 plumage is very oily, the bird when in the water is 

 clothed with a pellicle of air shining like silver. The 

 feathers on the neck are quite minute and set very 

 closely together, so that they more resemble a furry 

 covering than anything else. 



