356 Descriptions of the Groups of Birds 



their perch, for the purpose of killing it, before they attempted 

 to swallow it. In a specimen of the Dacelo, which has lived for 

 some years in the zoological gardens, I could never discern any 

 jerking motion, analogous to that of our native kingfisher. — 

 Bechstein attests the irreclaimableness of the captive roller. 



From the foregoing details, it will sufficiently appear that 

 these three families are very intimately allied ; composing a 

 distinct natural group, which, as such, should be recognized 

 by a systematic name. 1 propose for it, therefore, that of Cy- 

 lindrirostres, as the best I can devise at present: the system 

 of nomenclature which I have adopted requiring that groups 

 of this value should be designated from the beak, in order that 

 their terminology should be in accordance. I shall be glad, 

 however, to substitute any better name that may be suggested. 



The two families of jacamars and todies claim our next con- 

 sideration, as being most nearly allied to the preceding. I 

 am unaware that they have ever previously been especially 

 approximated : nor, perhaps, is the relation between them 

 quite so close as in the instance of the rollers, bee-eaters, and 

 kingfishers ; but it is nevertheless evident, and particularly 

 manifest in the structure of the tongue, and of the digestive 

 organs. 



As compared with the previous group, the birds now un- 

 der consideration present a slighter conformation, obviously 

 incapable of violent and protracted exertion. The skin is ve- 

 ry thin and delicate : the plumage soft : and the habits are 

 precisely those of the weaker fly-catchers. I make the latter 

 qualification, because certain of the larger Tyrannida, (Ame- 

 rican tyrant fly-catchers), have been seen to plunge after fish ;* 

 affording thereby additional proof, — if any were required, — 

 of the insufficiency of habit alone to indicate affinity : these 

 large Tyrannid<e also throw up their food, and catch it in the 

 throat, f The skeleton of the tody approximates that of the 

 kingfisher, except that the sternum is shorter, with its keel 

 considerably less developed : yet the pectoral muscles (of the 

 specimen I dissected) were remarkably full, the bird being 

 heavy, fleshy, and compact. The jacamar's sternum ap- 

 proaches nearer to that of the bee-eater ; but is also very much 

 shorter, weaker, and with a shallower keel : the curving form of 

 its four bony projections, caused by the double emargination 

 of its hinder edge, imparts to it a peculiar character : these 

 projections first tend outwardly, then narrowing, incline to- 

 ward the medial plane, and again slightly diverge from it, the 

 outer expanding at their tips : divested of them, the front view 



* Swainson. f Nuttall. 



