446 ICTERID^. 



is a very common species within our region. Aniblycercus has been placed both with 

 Cassicus and Cassiculus, but no doubt it has characters to distinguish it from both those 

 genera. In the first place the nostrils are covered by a hard horny operculum, leaving 

 the nasal orifice a comma-shaped slit, the tail of the comma being directed outwards. 

 This structure is not found in the more normal Cassicinae, and we have had to modify 

 Mr. Sclater's characters in order to include Amhlycercus. This operculum is not like 

 the membranous covering of the nostril in the other subfamilies of Icteridse, being as 

 hard and horny a substance as the sheath of the bill itself. The culmen is straight, 

 and the points of the jaws rounded horizontally and flattened ; the feet are stout, and 

 the tarsi comparatively longer than in Cassicus. The wings are short and very much 

 rounded ; the fourth, fifth, and sixth quills are subequal, and slightly longer than the 

 seventh, eighth, and ninth, the third equals the seventh, the second is about equal to 

 the longest secondaries, and the first is much shorter still. The tail is much rounded. 



The short, rounded wing presents another obvious point of difference from Cassicus 

 and Cassiculus. 



As in Cassiculus the feathers of the lower back are normal, the barbs being fully 

 furnished with barbules. 



1. Amblycercus holosericeus. 



Sturnus holosericeus, Licht. Preis Verz. Mex. Yog. p. 1 (c/. J. f. Orn. 1863, p. 55) '. 



Cacicus holosericeus, Salv. Cat. Strickl. Coll. p. 262^- 



Cassicus holosericeus, Scl. Ibis, 1883, p. 163'; Boucard, P. Z. S. 1883, p. 445*; Tacz. Orn. Per. ii. 



p. 415 \ 

 Amblycercus holosericeus, Scl. Cat. B. Brit. Mus. xi. p. 337 °. 

 Amblyramphus prevosti, Less. Cent. Zool. p. 150, t. 54^. 

 Amblycercus prevosti. Cab. J. f. Orn. 1861, p. 10'; Cass. Pr. Ac. PMl. 1867, p. 73'; Lawr. Ann. 



Lye. N. Y. ix. p. 104 " ; Frantz. J. f . Orn. 1869, p. 302 '\ 

 Cassiculus prevosti, Scl. P. Z. S. 1856, p. 301''; 1859, pp. 365", 380'*; 1860, p. 276"; 1864, 



p. 174"; ScL & Salv. Ibis, 1859, p. 19 "; 1860, p. 34"; P. Z. S. 1864, p. 353"; 1870, 



p. 836"°; Moore, P. Z. S. 1859, p. 57"'; Lawr. Ann. Lye. N. Y. vii. p. 297"; Ann. Lye. 



N. Y. viii. p. 180 '^ Salv. P. Z. S. 1867, p. 142""; 1870, p. 190"; Sumicbrast, Mem. 



Bost, See. N. H. i. p. 553"'. 

 Cassicus prevosti, Lawr. Bull. U. S. Nat. Mus. no. 4, p. 23 "' ; Nutting & Ridgw. Pr. U. S. Nat. 



Mus. vi. pp. 383"', 402"°. 

 Cassicus, sp.?, Bp. P. Z. S. 1837, p. 115 '°. 



NigerrimuB, unieolor; rostro eburneo, pedibus nigris. Long, tota 9*5, alse 4*2, caudse 4'4, rostri a riotu 1'2, 



tarsi 1'3. (Descr, exempl. ex Jalapa, Mexico, Mus. nostr.) 

 5 mari similis. 



Eah. Mexico '^ {Beppe S SalU ^^), valley of Mexico {White ^^), hot and temperate regions 

 of Vera Cruz (Sumichrast ^^), Jalapa (de Oca ^^), Teotalcingo and Playa Vicente 

 {Boucard^% Guichicovi, Sta. Efigenia {Sumichrast^''), Yucatena {Gaumer^}; Beitish 

 HoNDUKAS, Belize {Blancaneaux)-, Guatemala {Yelasquez^^, Constancia^), YzabaU^, 



