THE TONGUES OF BIRDS. 



1009 



Fig. 5. 



of the nuthatches, while coustructed on the same plan as those of the 

 titmice, are more complicated, and resemble a series of rods placed side 

 by side. 



The tongues of swifts and swallows (Plate 1, figs. 1-3), just referred to, 

 maybe called typical insectivorous tongues, since they are found in birds 

 whose food consists largely, if not entirely, of insects. 

 This style of tongue is slightly fleshy, but not so 

 thick as in the seed eaters, and in a great many 

 si)ecies bears, toward the base, numerous papilhe, 

 while in others papilke are distributed more or less 

 regularly over the tongue. These may be small and 

 blunt, or they may assume the form of spines; in any 

 case their object appears to be to work food backward 

 toward the gullet. Furthermore there is often a plen- 

 teous supply of sharp backwardly directed points about 

 the glottis, all to the end that food may glide safely 

 past the windjiipe. The tongues 

 of owls (Plate 2, fig. 5), while hav- 

 ing an individuality of their own, 

 are intermediate between those 

 of the goatsuckers and the diurnal birds of prey, 

 being rather fleshy and armed with small spines 

 on the posterior half. In some birds of prey there 

 is a system of large pores opening on the base of 

 the tongue, and in advance of the glottis. 



Many water birds, such as gulls, sandpipers, 

 rails, and herons, may also be said to have simple 

 tongues, and so do at least some of the pigeons 

 and fowls. From their simplicity it would seem 

 that the tongues of these birds do not play an im- 

 portant part, unless, indeed, the slender tongues 

 of some of the snipe family have a delicate sense 

 of touch which enables them to discriminate in 

 the matter of food, and this, from the horny con- 

 dition of the tip, seems rather improbable. 



There are other types of tongues found in other 

 groups of birds, while there are many birds whose 

 tongues have an individuality of their own and 

 decline to follow any general pattern; in fact, 

 when we come to know more about the tongues 

 of birds, that the exceptions are as numerous as 

 the resemblances, or, as with the votes on a preliminary ballot, there 

 are many scattering. 



The humming birds, so far as known, have a uniform pattern of 

 tongue (Plate 2, fig. 12), long and slender, deeply cleft, with each slender 

 branch bordered with a delicate inroUed membrane, which gives the 

 NAT MUS 95 64 



