The Zoologist— Februarv, 1 870. 2007 



some cases great differences in shape seem of scarcely more than 

 specific consequence, as is especially the case in the genus Simo- 

 rhynchus. The bill in the great majority of species is more or less 

 compressed, sometimes excessively so ; it is frequently, however, 

 nearly as wide as high at the base, and more or less subulate. The 

 contour of the bill in many instances deviates from an ordinary 

 standard so much that the shape may almost be called monstrous. 

 A striking peculiarity of the bill in several genera is the presence 

 of supernumerary elements or accessory pieces, taking the form of 

 salient protuberances. These are usually developed on the culmen ; 

 in one instance on the gonys ; in one at the angle of the rictus; 

 in several along the feathered base of the bill. Besides these 

 appendages, there are often found grooves and ridges on the 

 sides of one or both mandibles. The culmen is alw^ays more or 

 less convex ; in one instance it is bi-convex. The tomial edges of 

 the mandibles are more or less sinuate: sometimes nearly straight; 

 usually decurved at the tip, and slightly notched; in one instance 

 recurved. The rictus is ample.* The mandibular rami approach 

 each other with a very narrow angle, and soon join, producing a long 

 gonys, which is usually nearly straight. One genus has a very convex 

 gonys; in two others the gonys runs the whole length of the bill, 

 there being no mandibular rami proper. The bill is entirely horny, 

 except in two species, in which a soft membrane overlaps the base of 

 the upper mandible; and in a third, where a peculiar knob is not 

 strictly corneous. 



The nostrils are basal, lateral, marginal, impervious ; usually linear, 

 or narrowly oval ; in a few instances placed further from the com- 

 missural edge of the upper mandible, and nearly circular. The nasal 

 fossae are usually very evident; are sometimes hidden by feathers; at 

 others are wholly wanting. The extension of the feathers into the 

 nasal fossae varies in degree, when it occurs. In just about half the 

 species the nostrils are naked ; these usually have no true nasal fossae. 

 In the other half fossae occur; entirely obtected by feathers in three 

 genera ; partially covered in the rest. The significance of these 

 features will receive further attention below. 



The wings are short. In no instance do they, when folded, reach 

 to the end of the tail. In one species they are so undeveloped in their 



* lu two genera, in wbich the excessive compression of ihe bill produces a very 

 conslriuted rictus, its amplificaiiou is provided for by means of a dilatable skin at the 

 angle of the mouth. 



