1K82. 1 



ANATOMY OF THE INDIAN DARTER. 



211 



and neck, which may be compared to that of a man poising a spear 

 or harpoon before throwing it. Arrived within striking-distance, 

 the Darter suddenly transfixes, in fact bayonets, the fish on the tip 

 of its beak with marvellous dexterity, and then immediately comes 

 to the surface, where the fish is shaken off the beak by jerking of 

 the head and neck (repeated till successful), thrown upwards, and 

 swallowed, usually head first. 



A study of the neck in the recently dead bird leaves little doubt 



Fig. 1. 



a 



B' 



a 





Diagram to show the mechanism of the " kink" of the neck in the Darters. 



a, head and anterior moiety of neck (1st to 7th cervical vertebra) ; it, posterior 

 moiety of neck (from the 9th cerTieal vertebra to thorax) ; 8, 8th cer- 

 vical vertebra; D, "Donitz's bridge," on the 9th cervical; /, the two 

 flexor muscles (vide text) ; e, the extensor muscle (the longus colli ante- 

 rior). In fig. 1 the flexor muscles are supposed to be acting, bending 

 back the anterior part of the neck on the 8th cervical ; in fig. 2 the 

 extensor muscle has opened out the anterior genu formed by the 8th cer- 

 vical, thereby protruding the apex of the beak (marked' B in fig. 1) 

 to B'. 



as to the mechanism by which this peculiar impaling of the prey is 

 effected. The 8th cervical vertebra is articulated, as has already 

 been described, with the 7th in such a way that the two cannot 

 naturally be got to lie in the same line, but form an angle, open 

 forwards, of about 145°, when the two bones are stretched as far as is 

 possible in that direction. Behind, its articulation with the 9th 

 cervical is such as to permit it to be bent back at an angle a little 

 greater than 90° with that vertebra, beyond which extent, however, 



14* 



