274 REPTILIA. 



THE SECOND FAMILY OF THE SAURIANS — 

 Thi: Lizards, — 



Is distinguished liyits slender, extensililo, and forked tongue, as hi the Snakes; by its lengthened body 

 and rapid gait ; tiie feet have each five toes fnriiis-lied with claws, ^\hieh are separate and unequal, 

 more particularly those behind; their scales, \indrr the belly and around the tail, are disposed in 

 parallel transverse bands ; their tympanum, T\diich is on the upper part of the liead, is membranous 

 and shallow; a production of the skin, split longitudinally, and which closes by a sphincter, protects 

 the eye, beneath the front angle of which is a vestige of a third eyehd ; their false ribs do not form a 

 complete circle ; the males have a double penis ; and the anus is a transverse aperture. 



The species are very numerous and much varied, and we subdivide them into two great genera. 



Thc Monitors (recently termed, by a singular mistake, Tupriianibls), — 

 Are the largest of thc whole tribe; th^'y have teeth in both jaws, but none on the palate, and the 

 greater number have the tail laterally compressed, in adaptation to aquatic habits. Frequenting the 

 vicinity of the haunts of Crocodiles and Alligators, it is said that they give warning, by a whistling 

 sound, of the approach of those dangerous reptiles, and hence, probably, their names of Sai'vegonh? 

 and Monitor, though this is not quite certain. 



They dn ide into two distiiief groups. The (irst, or that of 



Tiip: Monitors, properly so called, — 

 Are known l)y their numerous small scales upon the head and limbs, the belly, and around the tad, 

 ■which latter has a keel above, composed of a doable range of projecting scales. Their thighs do not 

 exhibit that range of pores found in most other Saurians. All are from the ancient continent. 



Two species, in Eg;ypt, liave In-en considered the types of separate subdivisions; tlie Nilotic ^M. {Lnc. nllofira, 

 Lin.), of Varamis, and the Ground M. {L. sciiicusy Merrem), of Punmmosaurus, both of Fitziii;,^er. Africa and IiKiia 

 produce manymoi'i*, with .sharp(.'r teeth and still more compressed tail. 



The othrr groii[i of Monitors has angidar plates upon thc head, and great rectangular scales upon 

 thc belly and around the tail. The skin of their throat is invested with small scales, and forms two trans- 

 verse folds. They have a range of pores on the inside of each tliigh. Two subdivisions are required. 

 The first, or that of 



The Dragonets {Crocodiluni.s, Spix; Jda, Gray), — 

 Is distinguished by caudal crests, like those of thc Crocodiles, formed of raised scales; their tail is 

 compressed. Such is 



The Great I), of Guiana {M. crocodilhius), Merr.), ^vhicll attains a length of six feet, and is eaten. Tliere are 

 various others in the hot ret^ions of Aiiieiica. 



The Kestrictkd Monitors {Monitor, Fitzingcr), — 

 Have no keeled scales either on the back or tail ; their teeth arc denticulated, but with age the hind- 

 most become rounded. 



Some, more particularly termed Sauvegardes^ have the tail more or less compressed, and the belly scales loni^^er 

 than broad ; they frequent the borders of water. One, in Brazil and Guiana, attains to six feet in length. It runs 

 swiftly on the ground, and takes to the waterwhen pursued, iuin which it plunges, hut does not swim -, it devonrs 

 all sorts of insects, reptiles, the eggs of poultry, &c., and nestles in lioles which it bui-rows in the sand. Its ih ■^h 

 and eggs are eaten. 



Others, termed Amfeva, merely differ in having a round tail, covered, as is also thc l}i.lly, witli transverse ran^-'^s 

 of keeled scales, which on the belly are broader than long. They are American anirnats, wliicli resemble uiir Lriaids 

 extremely, but, besides wanting molar teeth, the greater number have no collar, and all have minute scales on the 

 throat; their head, also, is more pyramidal tlian in the Lizards, and they have no bony plate over the orbit. 



The Lizards, properly so called, — 

 Form the second great genus of this tribe. Tiicy have the hack portion of the palate armed wUh two 

 ranges of teeth, and are otlierwise distinguished from the i)reccding animals by a cnllar round the 

 neck, which is formed by a transverse range of broad scales, separated from those of the bellv bv a 

 space covered with small ones like those of the throat, and also by a part of the bones of the skull 

 advancing over the temples and orlnts, so that the ^diole head is defended by a bony cas(|ue. 



The species are very numerous, and many are found in Europe [though two only in this counti-y, L. aqilia, whi.-h 

 is comparat.'Vely rare, and L. viripurc, which, unlike the ntlicr, is ovovi\'iperniis, as in the ^'i|)L■rs, and extremely 



