456 MOMOTID. 
the genus readily divide into two groups—one containing these with the crown blue or 
black with a blue cincture, the other those with a chestnut head. The number of 
species admitted by Mr. Sharpe is eleven; Mr. Sclater recognizing ten in 1857. Of 
these five occur within our limits, viz. three of the first section and both the species of 
the second, which is peculiar to Western Mexico and Guatemala. 
The bill of Momotus is stout and compressed, the culmen curved and transversely 
rounded without any definite ridge, the serrations of the tomia are large and extend 
along the middle portion of both maxilla and mandible; the antrorse loral feathers 
when directed forwards reach as far as the nostrils without covering them; the nostrils 
themselves are nearly round, and are at the extremity of the nasal fossa, with a 
membrane behind. The tarsi as compared with the wing are rather long: the tail 
consists of twelve feathers, the outer pair reaching a little beyond the ends of the 
under tail-coverts; the middle pair are usually trimmed by the bird so as to leave a 
spatule at the end. 
a. Pileus aut ceruleus aut niger ceruleo circumcinctus. 
1. Momotus lessoni. 
Momotus lessoni, Less. Rev. Zool. 1842, p. 174°; Des Murs, Icon. Orn. t. 62°; Scl. P. Z. 8. 1856, 
pp. 189°, 285°; 1857, p. 253°; 1859, p. 387°; Moore, P. Z. S. 1859, p. 547; Scl. & Salv. 
Ibis, 1859, p. 181°; P. Z. S. 1870, p. 837°; Salv. Ibis, 1860, p. 100°; 1872, p. 321”; 
P. Z. 8. 1867, p. 150°; 1870, p. 201"; Cat. Strickl. Coll. p. 413%‘; Lawr. Ann. Lyc. 
N. Y. vill. p. 178"; ix. pp. 1177, 204'7; Bull. U. S. Nat. Mus. no. 4, p. 29"; v. Frantz. 
J. f. Orn. 1869, p. 311”; Boucard, P. Z. 8S. 1878, p. 48°; 1883, p. 45371; Sumichrast, 
La Nat. v. p. 289”; Nutting, Pr. U. S. Nat. Mus. v. p. 399”; vi. p. 887%; Ridgw. Pr. 
U.S. Nat. Mus. v. p. 501”; x. pp. 582”, 591°"; Zeledon, An. Mus. Nac. Costa Rica, 
1887, p. 119°; Cherrie, Auk, 1892, p. 322”; Richmond, Pr. U.S. Nat. Mus. xvi. p. 510*. 
Momotus psalurus, Bp. Compt. Rend. xxxviii. p. 659 (1854) *’. 
Prionites psalurus, Cab. J. f. Orn. 1861, p. 255 ”. 
Prionites momotus, Bp. P. Z. 8. 1837, p. 114°. 
Supra olivaceo-viridis, capite summo nigro argenteo-ceruleo circumcincto, ad nucham cyaneo-purpureo tincto 
nigro distincte marginato; capitis lateribus nigris, ceruleo anguste limbatis: subtus paulo rufescentior, 
gula viridi tincta, plaga pectorali nigra ceruleo limbata; alis extus cerulescentioribus; cauda quoque 
cerulescente, rectricibus duabus mediis nigro terminatis. Long. tota circa 15°5, ale 5:2, caude rectr. 
med. 8:5, rectr. latr. 3-0, rostri a rictu 1-7, tarsi 1-1. (Deser. feminse ex Izamal, Yucatan. Mus. nostr.) 
6 feminee similis. 
Hab. Mrxico, Xacaltepec (Deppe, in Mus. Berol.), Orizaba, Cordova (Sallé+, Sumi- 
chrast **), Huatusco, Cuichapa (Ferrari-Perez), Vera Cruz (W. B. Richardson), 
Playa Vicente (Boucard®, M. Trujillo), Teotalcingo (Boucard®), Atoyac, Teapa 
(Mrs. H. H. Smith), Chimalapa (Sumichrast 18, W. B. Richardson), Guichicovi 
(Sumichrast '$ *?), Temax *1, Buctzotz and Peto in N. Yucatan (G. F. Gaumer), 
Merida (Schott 1”); British Honpuras, Cayo and San Felipe in the western 
