28 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



ment is in this, as in so many other cases, pnictieally impossible.' The 

 key is therefore confessedly to a large extent artificial, the main object 

 sought being the easy identification of the genera. 



KEY TO THE GENERA OF FKlX(iILLID.E. 



a. Mandibular rami very short (less than one-fifth as long as gonys); width of man- 

 dible at base nearly equal to length of gonys (sometimes greater); nasal fossaj 

 obsolete, the nostril bored directly into basal lateral margin of the horny rhino- 

 theca; commissure not abruptly defiexed basally, or else- l^asal width of man- 

 dible greater than length of gonys. ( Coccothramtex. ) Hesperiphona (p. 37) 



aa. Mandibular rami longer (at least one-third as long as gonys); width of mandible 

 at base much less than length of gonys; nasal fosste more or less obvious (some- 

 times, however, hidden by small feathers); commissure abruptly defiexed 

 basally. 

 h. Mandil>ular rami less than one-half as long as gonys; nasal fossae shorter, more 

 or less hidden by tuft of antrorse latero-frontal plumules. 

 c. Maxilla and mandible with tips falcate and crossed. {Loxise. ) . . .Loxia (p. -46) 

 cc. ]Maxilla and mandible with tips neither falcate nor crossed. 



(/. Culmen strongly curved; ])ill very short and thick, the distance between 

 nostrils not less than half the length of gonys. {Pyrrhulie.) 

 f. Width of mandible at base greater than length of maxilla from nostril; 

 pileum (or at least forehead) black; wings and tail at least partly pur- 

 plish black Pyrrhula (p. 56) 



ee. Width of mandible at base less than length of maxilla from nostril; pileum 

 without black; wings and tail without purplish black. .Pinicola (p. 58) 



^The arrangement followed in the following pages is as follows: 



Group Coccothraustese. — Genus Hesperiphona. 



Group Loxiae. — Genus Loxia. 



Grouji Pyrrhulae. — Genera Pyrrhula, Pinicola. 



Group Fringillae. — Genera Leucosticte, Acanthis, Carduelis, Spinus, Loximitris, 

 Astragalinus, Carpodacus, Passer. 



Group Calcarieae. — (ienera Passerina, Calcarius, Rhynchophanes. 



Group CalamospizaB. — Genus Calamospiza. 



Group Spizae. — Genus Spiza. 



Group Chondestese. — Genera Chondestes, Pooecetes. 



Group Ammodrami. — Genera Passerculus, Centronyx, Coturniculus, Ammodramus. 



Group Zonotrichiae. — Genera Plagiospiza, Aimophila, Amphispiza, Junco, Spizella, 

 Zonotrichia, Brachyspiza, Melospiza, Passerella, Oreospiza, Pipilo, Melozone, 

 Arremonops, Arremon, Lysurus, Atlapetes, Buarremon, Pselliophorus, Pezopetes. 



Group Geoapizae. — Genera Platyspiza, Camarhynchus, Geospiza, Cocornis. 



Group Haplospizse. — Genera Acanthidops, Haplospiza, Sicalis, Euetheia, Melano- 

 spiza. 



Group Sporophilae. — Genera Loxipasser, Pyrrhulagra, ]SIelopyrrha, Sporophila, 

 Amaurospiza. 



Group Cyanospizae. — Genera Cyanospiza, Cyanocompsa. 



Group Oryzoboreae. — -Genus Oryzoborus. 



Group Guiracae. — Genera Guiraca, Zamelodia, Pheucticus. 



Group Cardinaleae.— Genera Pyrrhuloxia, Cardinalis. 



Group Pitylese. — Genera Pitylus, Caryothraustes, Rhodothraupis, Saltator. 



^ In the Asiatic genus Mycerohas. 



