OF GALLINACEOUS BIRDS AND TINAMOUS. 153 



fourth. His fifth Order, " Grallatorise," and his sixth, or " Palmipides," are named 

 after a different principle. Cuvier's " Families " are named in the first class from the 

 habits of the birds — " Accipitres Diurnae " and " Accipitres Nocturnse ; " the third 

 " Order," the " Scansorise," is also named on the same principle, or from the habits of 

 the birds. He has no " Families " in the scansorial and gallinaceous " Orders ; " and 

 the Families of the " Passerinse " are all named from the beak, viz. " Dentirostres," 

 " Fissirostres," " Conirostres," and " Tenuirostres : " this last "Family" is a curious 

 assemblage of genera ; it contains Sitta, Certhia, Trochilus, Upupa, Merops, Prionites, 

 Alcedo, Todus, and Buceros. After this, let no modest young ornithologist be afraid of 

 thinking for himself, when this great zoological chief has left us such a jumble. 



The " syndactyle " division of Cuvier's " Tenuirostres," the " Fissirostres," and the 

 Scansorial birds ought to be placed in very close contiguity ; and I have been more 

 struck with the dovetailing of these very interesting groups than with that of any others 

 in the class. One of the first things to be done in the study of these three conter- 

 minous families is, for the time, to forget the peculiar modifications of the bill and the 

 feet, and to look a little more deeply into the matter. Take the sternum alone in 

 these three groups, and how large an amount of modification do we have ! and yet the 

 study of its development shows how slight and how gentle are the changes — how much 

 is due to arrest in one, to overgrowth in another. The breast-bones of Caprimulgus 

 and of Cuculus are almost identical in shape : the same part in Buceros is like that of 

 the fledgeling Cuckoo, — the inner portion of the hyposternal piece not being lost along 

 the margin of the entosternura. The sternums of the Toucan, the Woodpecker, the 

 Plantain-eater, and of the Kingfishers {Dacelo, Alcedo) are very nearly alike ; that of 

 Podargus belongs to the same style, but is especially like the sternum of some of the 

 more delicate-billed Kingfishers. All these latter species have the hyposternal element 

 forked. But the pelvis and the skull show just the same kind of facts, and prove the 

 close relationship of these groups ; and it would require the space of a goodly volume 

 to give the matter in its fulness. 



The "Fissirostres " are not a little heterogeneous. The Swift (Cypselus) seems to 

 have barely escaped being a Swallow ; and the abortion of the inferior laryngeal muscles 

 and of the symmetrical caeca cob is rather startling to one who has just been studying 

 the true sylviine Hirundines. Must we set down to " teleology " alone the sudden 

 overgrowth in the Swift of the sternum and the wing-bones, and the abortive develop- 

 ment of its legs and feet ? Without leaving the family of the Warblers, the Swallows 

 and Martins have taken on the gaping mouth, the long wing, the forked tail, and the 

 tiny feet of the Swift, but not to the same degree. Whilst they retain all the true 

 sylviine structures, they overlap the "Fissirostres" on their cypseline border, and 

 might receive the title " Swift-like Flycatchers " {Muscicapcs cypseliform.es). 



A very large amount of work has to be done for the " Scansores " and their ornithic 

 neighbours, not merelv in tracing the development of the skeleton, and especially the 



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