414 LOWER VERTEBRATES. 



The Australian moloch, Moloch horridus, is one of the most repulsive creatures of 

 nature. While many of our lizards are protected by thorny scales, and some of the 

 Phnjnosonias have the head armed with horns, the moloch actually bristles with 

 strong, conical spikes, those surmounting the crown and those over the eyes being par- 

 ticularly long and stout. On the back of the neck is a large rounded protuberance 

 covered with spines and having the appearance of a second head. The larger spines 

 of the back and sides are simply conical growths of skin capped by a thin horny cover- 

 ing, and supported by surrounding dermal outgrowths of a similar nature, though 

 of smaller size. 



XioZejoAis, a native of the Malay Peninsula and China, is represented by but a 

 single species, Z,. sulcatus, which reaches a length of about twenty inches. The 

 genus is characterized by having the tympanum naked ; the scales small and without 

 keels, the femoral pores present, and by having, and chiefly, the skin of the sides of 

 the body capable of expansion into wing-like organs, which are supported by very 

 long anterior sjjurious ribs. When the animal is in a state of repose, or is simply 

 wandering among the branches, these organs are appressed to the sides of the body 

 and appear as mere longitudinal dermal folds. But when wishing to pass to some re- 

 mote position, or if merely agitated by sudden fear or anger, the six anterior ribs, 

 which are greatly elongated, are brought forward, expanding the membranous skin, to 

 which the fore and hind limbs are juxtaposed, and the thus greatly expanded reptile 

 sails off to a neighboring tree, as gracefully as the flying-squirrel. These lizards are 

 naturally very active, and will defend themselves with tooth and nail on being cap- 

 tured. In confinement, however, they soon become tame, and feed on rice and soft 

 fruits. 



The genus Stellio has the tympanum naked and the body depressed ; the scales are 

 spiny on the tail and unequal in size. No pores are present. S. tuberculatus inhabits 

 India, and is dusky brown above, speckled with black, and below whitish passing into 

 green on the throat. They ha\e been found on the mountains of Thibet as high as 

 15,000 feet. Specimens over a foot in length are rare. 8. vulgaris, called 'hardim' 

 by the Arabs, is found in those countries bordering on the eastern Meditei'ranean, and 

 is particularly abundant about the ruins of ancient buildings, where, during the 

 warmer portions of the day, they may be counted by the hundreds. They are always 

 busy, scrambling over the hot surfaces of the stones after flies and ants, only stopping 

 to nod their heads, — a habit, by the way, which has resulted in the death of many an 

 innocent, the Mohammedans supposing that the reptiles are mocking in derision their 

 form of worship. Tlie hardims are of an olive-green color shaded with black, and 

 below a pale yellow. 



The members of the family Iguanid^ are plurodont lizards confined to the 

 warmer portions of the New World. The body, in the more typical forms, is laterally 

 compressed and supported by limbs M'hich are designed for an arboreal life, though 

 forms like Phrynosoma may be depressed and terrestrial, while others of different 

 habits may have the body adapted to an aquatic life. 



The genus Polychrus has the quadrangular head covered with numerous appressed 

 shields; the back without a crest; the skin of the gullet compressed into a small 

 dewlap, and the body covered with smooth scales, which allow the changes in colora- 

 tion below to be easily studied. P- mannoratus, the marbled Polychrus, inhabits 

 Brazil and Central America. 



The genus Iguana, the one most typical of the family, has the head pyramidal, 



