FALCONID.*. 



and I lie power required of perceiving object* at very different distances 

 nud iu various directions, u well aa the rapidity of tbrir flight, seem 

 to render such a provision ueoewary. The eye* of birds are much 

 larger in proportion than those of quadrupeds, and exhibit also two 

 other peculiarities. The one is the manupium, a delicate membrane 

 arising at the bottom of the eye, and terminating at or near the edge 

 of the crystalline lens : the other is a ring of thin bony plates enve- 

 loped by the sclerotic coat Comparative anatomists do not seem to 

 be agreed as to the means by which birds obtain their power of vision, 

 whether by an alteration in the form or situation of the crystalline 

 lens, or by both, either or both of which, the greater quantity of 

 aquouus humour which birds are known to possess would seem to 

 facilitate. The existence of muscle attached to the inner surface of 

 the bony hoop of the sclerotica, and inserted by a tendinous riiig 

 into the internal surface of the cornea, as shonn by Mr. Crampton 

 ('Annals of Philosophy,' 1813), by which the convexity of the cornea 

 may be altered, gives a still greater scope of action, since with two, 

 or at the utmost three, varieties of powers the sphere of distinct 

 vision may be indefinitely extended. Whether the five speices called 

 the True Falcons possess, with their exclusive rapidity of flight, any 

 power of vision beyond their generic companions would be difficult 

 to ascertain ; but it may, while on this subject, be worthy of remark 

 that the irides of the gyrfaloon, peregrine, hobby, merlin, anil 

 kestrel are hazel-brown, or still darker, while those of all the 

 hawka, buzzard*, barriers, and kites are of various shades of yellow. 

 I refer only to adult birds, and do not remember a single exception." 



1, bony tint of a Golden Eagle ; 2, crystalline lcn of the same bird ; a, the 

 anterior surface, somewhat less convex than the posterior one. (Yarrrll.) 



Mr. Yarrell observes, that the number of bony plates forming this 

 circle in the Golden Eagle is fifteen; in the White-Tailed Eagle 

 there are but fourteen : and he adds, that the external convex form 

 of the bony ring in the Golden Eagle will be found to extend through 

 all the species of every genus of British birds, except the owla, in 

 all of which it is concave. 



In the Museum of the College of Surgeons are the following 

 preparations illustrative of this part of the subject. No. 1741. The 

 head of an eagle, with the eyes in situ. In the left eye the anterior 

 part of the tunics and the humours have been removed to show the 

 retina expanding from the oblique line by which the optic nerve 

 terminates, and the vascular processes of the marsupium extending 

 forwards from the centre of the optic fissure. In the right eye a 

 lateral section of the coats has been removed, together with the 

 humours and a great part of the retina, showing the uniformly dark- 

 coloured choroid, the thin but dense texture of the sclerotica, and 

 the rone of osseous plates which supports the projecting cornea. 

 The marsupium is preserved in situ. It is of an unequal quadrilateral 

 figure, broadest below, and extending upwards and inclined a little 

 backwards, with a slight convexity towards the nasal side of the eye- 

 ball. The Urge size of the eyes is worthy of notice. No. 1742 

 exhibits a longitudinal section of the eye of an eagle, showing the 

 oblique manner in which the optic nerve perforates the sclerotica 

 and iU extended termination, from which the retina expands in a 

 plicated manner: only the folds at its origin are here preserved. 

 The part* being minutely injected, the vascularity of the choroid is 

 shown : also the breadth of the ciliary zone, the breadth and thick- 

 ness of the bony imbricated hoop surrounding the base of the cornea, 

 the thickness of the cornea itself, and the huge sue of the anterior 

 chamber of the eye. No. 1743 is the eye of an eagle, with a 

 portion of the coats removed from one side, showing the folds of the 

 marsupial membrane, from which the colouring matter has been 

 removed. In No. 1538, above alluded to, portions of the eye and 

 eyelids with the nictitating membrane are preserved, showing the 

 situation of the two puncta lachrymalia, through which bristles are 

 passed along the ducts to the nose ; and in No. 1639, at the back part 

 of the preparation, the left eyeball is laid open, showing the 

 marsupial membrane. The right eyeball is entire, and the abductor, 

 attollens and deprimens oculi, together with the quadratus anil 

 pyramidalU muscles of the membrana nictitans, are well displayed. 

 See also No. 1540, as referrible to the organs of vision. No. 1796 

 exhibits the eyeball, with portions of the horizontal eyelids, the 

 vertical eyelid, or membrana nictitans, of an eagle. The quadratus 

 nictitantis may be observed to have a more extensive origin than in 

 the ostrich, and both muscles of the third eyelid are relatively larger. 

 The cornea is cut away, and the nictitating membrane raised, to show 

 the termination of the duct of ion gland, iu whii-h .-> 



brittle is placed. Bristles are also placed through the two puncta 

 lacbrvmalia. The round and slightly concave tarsal cartilage of the 



lower eyelid may be observed, the upper lid has no tarsal cartilage. 

 In No. 1797 the three eyelids of an eagle are exhibited, an 

 tarsal cartilage, which is raised as in the act of closing the eyes, is 

 shown. 



Aristotle divided the Palcmidm into 'Acroi, or AiVroi (Eagles), 

 'Ii'poKft (Hawks), and 'Irrb-oi (Kites), with many subdivisions. Mr. 

 Vigors is of opinion that the division 'l>o{ (Hierax) of Aristotle 

 comprises all the Falconida of Vigors which belong to the stirpes 

 or sub-families of Hawks, Falcons, and Buzzards. Pliny separates 

 the group into Aquila (Eagles) and Accipitret, a general t. TNI 

 comprising, as used by him, the rest of the PaUonida. The sub- 

 divisions of both Aristotle and Pliny do not differ much from the 

 subdivisions of some of the modern zoologists. 



Belon, beginning with the Vultures, proceeds from them to the 

 Eagles; thence to the Gerfault, which he gives as the Morphnos, 

 Morphna, Nittophonos, Plangos, Plancus, Plangus, and Clangus, of thu 

 Greeks, and Anataria of the Latins ; next he places the Orfraye, 

 which ho makes the Halurdta of the Greeks, the Aguista Piouibina 

 of the modem Italians, and gives Aguila marina as the Latin name. 

 He then treats of the Ouifragut aa the Phiuis of the Greeks, J /'"''" 

 barbata in Latin, recording it provisionally as a species of Vulture (IVtit 

 Vautour) and next describes the Buzzard (liuse ou Busard) as a kin.l uf 

 Bastard Eagle, and as the Gypactos, Percnopterus, or Oripelurgus, of 

 the Greeks. Then comes the Goiran, or Boudrec, which he describes 

 as living upon rats, mice, frogs, lizzards, 4c,, caterpillars, and some- 

 times slugs and serpents, asserting that it becomes very fat, and 

 that it la taken frequently in winter for the sake of its flesh, which 

 is good for food. This he supposes to be the Hitrar, allied I'hryno- 

 lochos by the Greeks, and gives Kubetariut A ccipiter as the Latin 

 name, Jean le Blanc, or Oyaeau Saint Martin, which he considers to 

 be the Pygargus of the Greeks, follows, and is succeeded by another 

 Oyseau Saint Martin, or Blanche-Queue. Belon then gives an account 

 of the Birds of Prey employed in falconry. The Sacre and her 

 Sacret, the Autour and her Tiercelet, the Fau-lVrdrirux (Circus?), 

 and the Falcons generally, with their Tiercelcts. He then describes 

 the Hobreau (Hobby ?), the Esmerillon (Merlin ?), the Espervier 

 (Sparrowhawk ?), the Lanier and Lancret, and the Creaserolle 

 (Kestrel?). Next follow the Butcher-Birds, then come the Kites 

 (Milan Royal, Milan Noir Milvus), and (the Cuckoo intervening 

 from a supposed similitude to the Birds of Prey) the Owls. 



Passing by Gesner, Aldrovandus, and Jonstou, we pause to notice 

 Willughby 's arrangement. He separates the carnivorous and rapacious 

 birds, called Birds of Prey, into the Diurnal (those that prey in thu 

 day-time) and the Nocturnal (those that fly and prey by night). The 

 following is his table of the Diurnal section : 



TK <-~. , [The more generous, called Eagles: thc Golden Eagle, 

 and tn j the *W. * M-ek Eagle. Ac. 

 cither . . . \Thc more cowardly and sluggish, called Vultures. 



Diurnal 



The Lesser, 

 called in La- 

 tin Accipi. 

 tra 



The more generous, 

 that arc wont to 

 be reclaimed and 

 manned for fowl, 

 ing, called Hawks, 

 which our fal- 

 coners distinguish 

 into .... 



Long- Winged, whose wings reach 

 almost a far as the end of their 

 train, as the Falcon, Lanner, fto. 



Short-Winged, whose wings when 

 closed fall much short of the end 

 of their trains, u the Goshawk 

 and Sparrowhawk. 



Thc more cowardly I The Greater. The Common Buz- 

 and sluggish, or | zard, Bald Buzsanl, ,w. 



i European : llntcher 

 1 Hirds or Shrike*. 



else indocile, and I 

 therefore by our 

 falconers neglect-] Thc Lesser 

 ed, and permitted 

 to live at large . ^ 



Exotic : Birds 

 Paradise. 



Of 



Ray, in his 'Synopsis,' follows Willughby, and both Hay and 

 Willughby place the Cuckoo after their Diurnal Birds of Prey and 

 immediately before the Nocturnal. 



Brisson's third order consists of birds with a short and crooked 

 beak, and the first section contains the genera Epervier (Hawk) 

 Aiglo (Eagle), and Vautour (Vulture). 



Unusous makes his first order, Accipitrct, consist of the genera 

 Vultttr, Falco, Strii, and Lanitu. The genus faleo contains the 

 elements of the different branches of the family of Falconidte. 



Without entering into the methods of Buffon, .Schoeller, and Scopoli, 

 we proceed to that of Latham, who made the Accipilra his first 

 order of Terrestrial Birds, containing the genera Vulture, Falcon, 

 and Owl. 



Pennant makes the Rapacious Birds (his first section) consist of 

 two genera only, namely, Falcon and Owl. 



M. de Laclpode placed the Birds of Prey (his seventh order) at 

 the head of his second division of bird*. His genera are Vullw 

 Oypaftot (Griffon), Aqttila, Attw, ffinu, Bvtto, Circtu. Milviu, Palm 

 mi. I ttiv> (Owl). 



M ]>iitm'-ril divided his first order, Rapacet, into three families: 

 the first Nudicollce, or Ptilodoreo, consisting of the genera t 

 rum/iAtu and Vailur ; the second Plumicolles, or Cruphodfcres, 

 containing the genera Griffon, Messager, Aigle, Buse, Autour, and 

 Faucou ; and the third the Nocturnes or Nycterins (Owb). 



