249 



I think they have quite sufficient distinctive characters to entitle them 

 to rank as an independent family), and not Prionitidce, as is done 

 hy some modern systematists. 



The Motmots are a purely tropical American family, occupying 

 an area nearly coequal with that of several other characteristic groups 

 belonging to the same fauna. From Southern Mexico, where two 

 species occur, they extend through Central America and some of the 

 more southern Antilles over the whole of the eastern portion of 

 South America as far southwards as south-eastern Brazil and Para- 

 guay, where a single species is found. Their true focus seems to 

 be Central America, where the greatest number of species and the 

 most characteristic forms occur. 



Concerning the spatulation of the two medial rectrices in some of 

 these birds, which has occasioned so much discussion, I am not in- 

 clined to agree with Waterton, who thinks that it is performed by 

 the bird with his own beak (see Wanderings, ed. 4, p. 114) ; nor 

 with Schomburgk, who attributes it to the form of the nest (Nau- 

 mannia, 1, pt. iv. p. 20) ; but I consider it a purely natural forma- 

 tion, which, like the denudation of the base of the bill in Corvus 

 frugilegus, does not become complete except in the adult bird. 



A similar formation occurs in certain groups of Humming-birds 

 {Spathura, Loddigesia, &c.) and among the Parrots in the genus 

 Prioniturus ; but in these cases the feathers are, I believe, produced 

 with the stem already denuded, and do not (as in Momotus) become 

 spatulated by the falling away of the intermediate barb. 



Familia Momotid.e. 



Rostrum longius quam caput, modice incurvum, plerumque com- 

 pressum, apice pauhilum uncinata ; mandibidarum marginibus 

 serratis ; oris angulis vibrissis munitis : nares basales, apertura 

 parva et rotundata : alee breves, rotundatce, remigibus quarta, 

 quinta et sexta fere aqualibus et longissimis : cauda, e rectri- 

 cibus decern aut duodecim, quorum duce externa abnormaliter 

 breves, elongata valde graduata, rectricibus duabus mediis lon- 

 gissimis et harum apicibus plerumque spatulatis : tarsi breves, 

 antea scutellati : pedes prehensorii, digito exteriore longo et 

 cxtm mediali usque ad medium, interiore autem brevi et ad 

 basin tantum cum medio conjuncto ; posteriore hoc paulo bre- 

 viore ; unguibus incurvatis et compressis. 



Genus I. Momotus. 



Momotus, Lath. Iud. Orn. i. p. 110 (1790). 

 Prionites, 111. Prodr. Syst. p. 224 (1811). 

 Bargp/io/tus, Vieill. Analyse, p. 48 (1816). 



Rostrum elongatum, compression ; mandibnlis jortiter serratis : 

 cauda elongata. 



Div. a. Cauda; rectricibus duodecim, harum duabus mediis spatu- 

 latis. 



