1014 



REPORT OF NATIONAL MUSEUM, 1895. 



iiuuierous, longer, and more slender, cbanging from barbs to bristles 

 and from bristles to liairs, until the transformation is complete and the 

 spear lias become a brusli ; ' or, if we strip ofi" the adaptive disguises, we 

 will find tbat the liyoid, whether long or short, is constructed on the 

 same plan, and may see at a glance that CeopMxviis and Sphyrapicm 

 are akin to one another. At the same time it is an equally easy matter 

 to tell considerable of the food and habits of a Avoodpecker from the 

 tongue, to make a guess as to the probable preference of the species for 

 animal or vegetable food, and to say whether it spears grubs, eats 

 insects, or probes after ants. Here the tongue apparently points two 



ways, not only indicating relationship, but 

 more than hinting at the dietary habits of its 

 possessor. 



The tongues of the swifts have a very close 

 resemblance to one another, so do those of the 

 swallows (Plate 1, figs. 1-3), and the two groups 

 are so much alike in this respect that it is 

 extremely difficult, if not impossible, to tell 

 them apart. Now externally swifts and swal- 

 lows are very much alike, their food and the 

 mode of taking it is identical, and yet struc- 

 turally the two are widely separated, ptery- 

 losis, skeleton, muscles, alimentary canal, all 

 being different. Here, then, if we followed the 

 tongue, we should be at sea, and in this case 

 we may feel pretty safe in saying that the 

 resemblances between the tongues of swifts 

 and swallows are due to the influence of food. 

 The case may be further strengthened by show- 

 ing that birds not very closely related to either 

 swift or swallow resemble them in the general 

 style of their tongues, and this is true of at least the cedar bird and one 

 of the trogons (Plate 1, figs. 4 and 5), Friotelns, while further examina- 

 tion will probably bring to light further resemblances. 



The owls furnish good examples of similarity of tongues arising from, 

 or at least correlated with, similarity in habits, for the genera Megas- 

 cops, Asio, Wyctea, Speotyto, and Strix have tongues built on the same 

 plan, the main difference being that tStrix, which is a long-faced bird, 

 has a long tongue. It might perhaps be assumed that because the 

 beak was long the tongue would of necessity be long also, but this by 

 no means follows, for the short tongues of the long-billed kingfishers 

 warn us that there is no necessity iu the case at all, and that the length 

 of the bill is no index to the length of the tongue. 

 The opposite state of aff'airs, differences among related birds, is well 



' Lucas, F. A. The Tongues of Woodpeckers. Bulletin No. 7, U. S. Department of 

 Agriculture, Division of Oruitliology and Mammalogy. 



Fig. 10. 



