45 



RAMPHASTID.E. 



RAMPHASTID^:. 



516 



lobes, of which the middle one is smallest, are an inch and a half in 

 length, with a surface convoluted, though in a less marked degree 

 than it is in reptiles. Between the anterior extremities of these 

 glands Mr. Owen found, in a female Ramphaslos Ariel, the ovary of 

 a triangular shape, and apparently healthy. The ova were like 

 minute granules, and disposed in a convoluted manner. The supra- 

 renal glands were imbedded in the posterior part of the ovary. The 

 oviduct, of the size of a crow-quill, commenced by the usual fimbriated 

 and wide aperture, was slightly tortuous at the commencement, and 

 then continued straight to the cloaca. 



Osseous and Muscular Systems. Certain parts of this system bear 

 upon peculiar functions performed by the Toucans, and are thus 

 described by Professor Owen : " The pectoral muscles as in the 

 Psittacidce, are but feebly developed, and the keel of the sternum is 

 of moderate size, not projecting more than half an inch from the 

 plane of the bone. The sternum has four notches at its posterior 

 margin. The clavicles, or lateral halves of the fureula, are here, as 

 in the Ptittacidce and Struthionida, separate ; they are an inch in 

 length, slender, pointed at their lower ends, and joiued to each other 

 and to the sternum by a ligament only." 



Foot of Toncan. a, Seen from below. 



" The peculiar motions of the tail called for a particular examina- 

 tion of that part. It is difficult to state the- precise number of the 

 caudal vertebrae, in consequence of the terminal ones being anchylosed, 

 requiring for this purpose the examination of a young specimen at a 

 period before the anchylosis take* place. In the skeleton of a Black- 

 Billed Toucan which I have examined, it would appear that three 

 vertebra are thus auchylosed, making the entire number of coccygeal 

 vertebras nine. The Woodpecker has also niue caudal vertebne, anil 

 this seems to be the greatest number found in birds. The first six 

 of these vertebra in the Toucan are articulated by ball-and-socket 

 joints, the ball and tlie socket being most distinct in the last two 

 joints. That between the sixth and the anchylosed vertebra; is pro- 

 vided with a capsule and synovial fluid ; the others have a yielding 

 ligamentous mode of connection. The spinous processes of these 

 vertebra, both superior and inferior, are of moderate size, but 

 smallest in the sixth, where the greatest degree of motion takes place. 

 The transverse processes, on the contrary, are large and broad, so as 

 almost wholly to prevent lateral motion. The first of the anchylosed 

 vertebrae is broad and flat, and of a rounded form, supporting the two 

 coccygeal glands : the last of these processes is compressed laterally, 

 and of the ordinary ploughshare form. The caudal vertebra: can be 

 inflected dorsad till their superior spines arc brought into contact 

 with the sacrum ; in the opposite direction they can scarcely be bent 

 beyond a straight line ; and it is to this structure of the bones and 

 joints that is to be attributed the capability in the Toucan of turning 

 its tail upon its back (as represented in the 'Zoological Journal,' 

 vol. ii., pi. xv.), the muscles presenting comparatively few peculiarities, 

 since the motion alluded to is remarkable rather for its extent than 

 the vigour with which it is performed. The principal elevators of 

 the tail are the sacro-coccygei superiores (sacro-suscaudiens of Vicq 

 d'Azyr). They arise from two longitudinal ridges on the inferior and 

 convex part of the sacrum, and are inserted into the superior spine 

 of the first six vertebra by detached tendons terminating broadly in 

 the anchylosed vertebras. The principal antagonists of these muscles, 

 the acro-coccygei inferiores (sacro-souscaudiens of Vicq d'Azyr), 

 pass over the first fire vertebra, and terminate in the sixth and 

 anchylosed vertebras ; their origins are wider apart than in the pre- 

 ceding pair of muscles, coming off from the margin of tho sacro- 

 sciutic notches. In the interval are situated small muscles passing 

 from the transverse processes to the inferior spines of the first six 

 vertebra;. From the limited nature of the lateral motions of the 

 tail, the muscles appropriate to these movements are feeble, especially 

 in comparison with those which are observed in the birds that spread 

 their tail-feathers in flight, in order to regulate their course during 

 that vigorous species of locomotion. These muscles are in number 

 two on each side, arising from the posterior extremities of the ischia, 

 and inserted into the expanded anchylosed vertebras. From the 

 disposition of these muscles it is obvious that after the proper eleva- 



AT. HIST. DIV. VOL. IV. 



tors have raised the tail to a certain height, they also become dorsad 

 of the centre of motion, combine their forces with the elevators, and 

 by this addition of power terminate the act of throwing up the tail 

 by a jerk. Mr. Vigors, in his observations on the living animal, 

 observes, that ' in these movements the tail seemed to turn as if on 

 a hinge that was operated on by a spring."' (Owen, in Gould's 

 ' Ramphastid.c.') 



We now proceed to give some examples of the Toucans and 

 Araearis. 



Ramphastidce. Bill enormous, vascular within; the margins 

 serrated. Wings short, rounded. Feet with two toes before and two 

 behind. (Sw.) 



Ramphastos. Bill smooth. Nostrils entirely concealed, and placed 

 at the edge of the thickened frontlet of the bill. Wings short, 

 rounded ; the four outer quills graduated and abruptly pointed. Tail 

 short, rounded. (Sw.) 



R. Toco appears to be one of the largest species, being 27 inches in 

 total length. The bill measures 7J inches; the wings 10 inches; the 

 tail, 7 inches; and the tarsi are 2 inches in length. A beautiful 

 figure of the bird, by Lear, is given in Mr. Gould's magnificent work. 

 The range of the species is very wide, perhaps wider than that of 

 any other, being distributed throughout the whole of the wooded 

 districts from the river Plata to Guyaua. 



R. Cuvieri. Beak hm"n!-< -Wick on the sides, with a large basal 

 belt and culminal line or greemsn-yellow, the basal belt being bounded 

 behind by a narrow line of black, and before by a broader one of 

 deep black, which is only apparent in certain lights ; the top of the 

 head and whole of the upper surface black, with the exception of the 

 upper tail-coverts, which are bright orange-yellow ; cheeks, throat, 

 and chest white, with a tinge of greenish-yellow, terminated by a band 

 of scarlet ; under surface black ; under tail-coverts scarlet. Total 

 length 24 inches; bill, 7^ inches; wings, 9 inches; tail 64 inches; 

 tarsi, 2 inches. (Gould.) 



This is a very rare bird and is found in the densely wooded districts 

 on both sides of the Amazon. 



tos Curicri. (Gould.) 



Ptemylossui. Bill smooth, less compressed; nostrils vertical, naked, 

 round, pierced on the upper surface of the bill, on tho edge of the 

 frontlet. Wings short, rounded. Tail lengthened, graduated. (Sw.) 



P. Humboldtii. Bill large in proportion to the body ; a band of 

 black occupies the culrnen from the base to the tip ; the remainder of 

 the upper mandible of a dull yellowish-orange, with the exception of 

 an indefinite mark of black which springs from each serrature, and a 

 fine line of the same colour surrounding it near the base ; lower man- 

 dible black, with the exception of the base, which is surrounded with 

 pale yellowish-orauge ; the head, back of the neck, throat, and chest 

 black ; all the upper surface, except a spot of scarlet on the rump, of 

 a dull olive; primaries blackish-browu ; under surface pale straw- 

 yellow with a slight tinge of green; thighs chestnut; naked space 



2 S 



