G R A 



part of the neck and bread, and in the white being mere 

 obfcure. 



QuiscALA. Violet, black ; tail rounded. Linn. Finis 

 jamaicenfis, Briff. Cornix purpurea, Klein. Fur-zed:, Kalm. 

 Jzanati, Ray. Black-bird, or maize-thief, Kalm. Tr. Pur- 

 ple ^rakle, Arft. Zool. 



Native of Mexico, and the warmer parts of America, 

 and the Weft Indies; fings finely, builds on trees, is de- 

 ftruftive to plantations, but ufeful in deftroying the noxious 

 jnfeas that infeft them. The flelh is black and unfavoury. 

 Its iize is about that of the black-bird, the male a little ex- 

 ceeding the female in bulk ; the bill and legs are black ; 

 tail long and cuneated, and with the wings purple ; the fe- 

 male entirely duflcy. 



Atthih. Greenifti-blue ; belly rufty ; legs blood-rcd, 

 Linn. Corvus JEgyptius, Haifeln. Egyptian gral/e. Lath. 



Size of a lark; and is fuppofed by HalTelquift to feed on 

 infe£ts, the remains of centipedes and fcorpions being found 

 in the ftomach. The bill is black ; neck with a longitu- 

 dinal rufty line each fide, and the claws black. 



LoNGiROSTRA. Erown, beneath ochre-yellow ; head and 

 neck black; band round the neck naked ar.d wrinkled; area 

 .of the wings white ; tail cuneated, black, and at the tip 

 white. , Pallas, &c. 



Native of- South America; length eight inches. This 

 ■ appears to be the fame fpecies as that dcicribed by Sonnini 

 , under the name of merle des Savannes. 



Sturnina. Hoary; fpot on the crown and back be- 

 ■, tween the wings violet-black ; tail and wings witli a tinge 

 ...of green, the latter with a double white ftripe. Pallas. 



Inhabits the Ozier banks of Dauuria ; the neft and eggs 

 refemble thofe of the tliriilli ; tlie plumage of the female 

 is dirty alh, with the back brown ; and the wings and tail 

 . deep black. 



IcTEROPS. Black ; band on the wings and body beneath 

 wllite ; the region of the eyes naked and wrinkled. Lath. 

 j.Le mainate afacejauni, Vieill. Telloiu faced graUe. 



Length feven inches and a half; bill comprefled ; noftrils 

 oval ; legs yellow and wrinkled. Native of New Holland. 



Cavane\'.si.s. Striated; abave tawny, beneath yellovv- 

 ifh ; head and chin varied with tawny and white ; tail wedged, 

 fharp and with the wings tawny. Gmel. Climbing graile. 



Inhabits the interior parts of Guiana ; is about ten inches 

 in length, and remarkable for climbing trees ; the bill is 

 black, about two ir.ches long, and a little curved; the legs 

 are alfo black. 



Carunculata. Cinereous; tail and quill-feathers 

 : black ; crown and chin with warty excrefcences. Gmel. 



Length fix inches ; and fuypofed to inhabit the Cape of 

 Good Hope. 



Melaxocepiiala. Head black, front white; back, 

 tail, and wing-coverts blueifh-aih, the laft with a tranfverfe 

 white iireak near the extremity. .Don. Grarula mehmoce- 

 pha/a. Lath. Lemaitiatea Icte noire, Vieill. Black-headed 



grakh. 



A fpecies recently difcovered in New South Wales ; its 



height is about eight inches ; the bill yellow, a htfle bent, 

 and formed at die bafe like that of the Tardus, or thrufh 

 tribe ; the tail three inches long ; the legs very long in pro- 

 portion, of a pale yellow ochre-colour, and armed with 



, ftrong blackilli claws. 



VililDls. Dull green; throat above brown and blackifli 

 varied ; under parts of the plumage whitilh, with fome 

 blackilh ftreaks ; wings blackifh, edged with white ; tail 

 blackifh, with white tip. Don. Gracula -viridis. Lath. 



jJjC mainate vert, Vieill. Green graile. 



X,ately found; the fpecies inhabits New Holland, and 



G R A 



appears to be very rare; the bill is ftrong, fomewhat in. 

 chning at the bafe, and the colour of horn ; the legs 

 blackifti. 



Cyanoti.s. Space about the eyes bare of feathers and 

 bright blue ; head black, with a white crofs on the hind 

 part ; upper part of the neck, body, fcapulars, wing- 

 coverts, and tail yellowiih-green ; breaft lead-colour ; plu- 

 mage beneath white. Don. Gracula cyanolis, Laili. L.e 

 mainale a oreilles bleues, Vieill. Blue eared greikle. 



Length twelve inches and a half; bill black ; legs blue " 

 black, with very hooked black claws. Native of Nev» 

 South Wales. 



- Picata. Greater part of the head, the neck ; tranf- 

 verfe band on the breaft, back, border of the wings, and 

 tail above nearly to the tip black ; throat, breaft, wing- 

 coverts, body beneath, and under furface of the tail-fea- 

 thers white. Don. Gracula picata. Lath. Le mainate pie, 

 Vieill. Pie grakle. 



Rather l;u-gcr than the black-headed grakle, and like 

 that fpecies inhabits the regions of Auilralafia ; the general 

 colour black and white, tiie former partially gloffed with 

 purple ; bill yellow, and correfponding in form with that of 

 the black-headed grakle ; and the legs lead colour. 



GRACULUS, the Shagge, a fpecies of Pelecanus; which 

 fee. — Alfo, a fpecies of Corvus ; which fee. 



GRADATION, the aft of afcending, ftep by ftep, to 

 any pitch or eminence : from the Latin gradus, degree, 



>^- . . . . 



Gradation, m Architedure, fignifics an artful difpofition 



of parts, rifing, as it were, by ilcps or degrees, after the 



manner of an amphitheatre : fo that thofe placed before do 



no differvice, but rather fervice, to thoft- behind. 



The painters alfo ufe the word gradation for an infenfible 

 change of colour, by the diminution of the teints and 

 Ciades. Sec below. 



GuAnATiON, in Chemiflry, is a kind of procefs belong- 

 ing to metals. It confills ni gradually raifmg, or exalting 

 them to a higher degree of purity and goodnefs, fo as to 

 increafe their weight, colour, confiftence, &c. 



Gradation, in hogic, is an argumentation, confiding 

 of four or more propofitions, fo difpofed as that the attri- 

 bute of the firft is the fubjedl of the fecund ; and the at- 

 tribute of the fecond is the fubjeil of the third, and fo on, 

 till the laft attribute come to be predicated of tlie fubjeft 

 of the firft propofition. As in Porphyry's tree ; man is 

 an animal ; an animal is a living thing ; a living thing 19 

 a body ; a body is a fubilance : therefore man is a iub- 

 ftance. 



An argument of this kind is liable to many fallacies; 

 both from the ambiguity of words and tilings ; e. gr. Peter 

 IS a man ; man is an animal 4 animal is a genus ; genus is an 

 univerfal ; therefore Peter is an univerfal. 



Gradation, in Painting, relates both to chiaro-fcuro 

 and to colour : that is, all the different degrees in which 

 light and dark, and .colour may be modified, are compre- 

 hended in it. 



An objefk receding froiW the light, and gradually lofing it, 

 becomes at its iartheft extremity obfciirely defined. A 

 coloured body, pure m- bright in teiiit, under the fame cir- 

 cumftances, gradnally diminilhes in clearncfs of hue througli- 

 out jts receding parts, and becomes dull and dark. By 

 fixing the fcalc of gradation in both tliefe particulars, effefts 

 of great force or great fimplicity may be produced. The 

 fcale of defcent being n-.ade rapid, great force will enfue, 

 from the ftrong oppolitioiis it promotes ; and the rcvcrfe 

 will take place when the degrees of defcent are prolonged, 

 and lefs contiraft thereby effected. The nature of the fub- 



jea. 



