218 FORMICARIID 2. 
Mr. Lawrence describes the female as resembling the male on the upper surface, but 
of a very deep chestnut-red on the under surface. The female of F. boucardi would 
thus appear to differ considerably, being decidedly grey above and lighter chestnut 
beneath. The type, which as well as the male has been kindly lent us by the authorities 
of the American Museum of Natural History, shows these differences ; but the tint of 
the under surface is not pronounced, and can be nearly matched in specimens of 
F. boucardi. . | | 
We do not know enough of this bird to be able to form a decided opinion as to its 
status with respect to /. boucardi. 
b. Nares operculate, rostrum quam caput longior, mandibule tomia levis. 
RHAMPHOCAENUS. 
Ramphocenus, Vieill. N. Dict. dW’ Hist. Nat. xxix. p. 5 (1819). 
Rhamphocenus; Scl. Ibis, 1883, p. 92; Cat. Birds Brit. Mus. xv. p. 260. 
Rhamphocenus is one of the most peculiar genera of Formicariide, and to whatever 
position it is assigned in the family it must occupy an isolated position. Cabanis and 
Heine place it at the head of their family Eriodoride—Terenura and then Ellipura and 
Formicivora following. Mr. Sclater includes it in the subfamily Formicariine, and places 
it between Terenura and Cercomacra. Weare not satisfied with either arrangement. The 
bill of khamphocenus is very long, the culmen slightly curved, with hardly any terminal 
hook and a very slight subterminal notch on the tomia of the maxilla and none what- 
ever on the mandible. The nostrils are situated a considerable distance beyond the 
frontal feathers ; they are elongated and overhung to some extent by a membrane which 
has a lobe near the middle. Rictal bristles are well developed. ‘The tarsi are covered 
behind by a continuous entire scutellum, which bears no signs of divisional sutures ; 
the toes are rather feeble, the hallux being rather long. ‘The wings are rounded, but 
present no peculiarity ; the tail in one section of the genus is long, much rounded, the 
rectrices being narrow: in the other section it is shorter and squarer. 
On the whole, we think Rhamphocenus best placed near Formicivora, notwithstanding 
the very different form of the bill and the structure of the nostrils. Both genera have 
well-developed rictal bristles, a feature not at all usual in Formicariide. 
Mr. Sclater divides Rhamphocenus into two sections—a long-tailed section and a 
short-tailed section *. This arrangement we follow.. One member of each section 
* Mr. Sclater places in the second section Microbates collaris, but we are doubtful if this is correct. Apart 
from its peculiar coloration, MZ. collaris has open oval nostrils, thus differing considerably from Rhampho- 
cenus. That Microbates is allied to Rhamphocceenus is obvious; both have similar bills, the mandible being 
destitute of any trace of a subterminal notch. This character might be used to separate these two genera from 
the rest of this section of the Formicariide, and the nostrils to divide them from one another. 
