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Show f;EXUAL HET.ECTION. J' ,\1:'1'11. The cau ·c, howvenomons Blnp::; ma_v perhaps be thonght clnngerous by their enemies. cver, of tho bright ·olours of the remains to be cxplnined, and this sexual scl ction. LacertilicL.-'rbe males of some, probauly of many }.;ind~ or lizard:; fight 1 o~cth cr from rivn.lr~r. 'J'hn::; the n.rborcal Anolis c1·isiatellus of 1 '. Am rica is cxt rcmeh pugnacious: "During tlto .-pring and early part of th.e '' summer, two adult males rarely moot withont a con" test. On ftrst seeing one another, they uod their hcacls '' up an(l down three or four times, at the sn.mo time '' cxpand.ing the frill or pouch beneath the throat; their " eyes glisten wiLh rngc, and after waving their tails " from side to side for a few seconds, as if to gather '' energy, they uart at each other furiously, rolling oYer " aml over, ar:.d holding firmly with their t eeth. The " conflict generally ends in one of the combatants losing " his tail, which is often devoured Ly the victor." The male of this species is considerably larger than tho female; ~r, and this, as far as Dr. Gunther has been able to ascertain, is the general rule with lizards of all kinds. The sexes often differ greatly in various extemn. character::-. The male of tho aboYe-mentionecl Anoiis is fnrni heel with a crest, which runs along the back and ta.il, and can be erected at pleasure; but of this crest tho female does not exhibit a trace. In tho Indian Cophotis ceylanica, the female possesses a dorsa.l crest, tllough much less developed than in the malo ; and so it is, as Dr. Gunther informs me, with the females of many Iguanas, Chamolions and other lizards. In some species, however, the crest is equally uevelopod in both sexes, as in the Iguana i~bbetculata. In the genus a:. Mr. "N. L. Austrn k pt these n.nimn.l.; nlivc for a co:l~iLb·au l e li :1:0 ;;co 'Lo.ml o.ntl Water,' July, 18G7, p. U. •CII.AP. XIL REPTILES. 33 Sitana, tho males alone are fu . h . throat-pouch (fiO' 33) h~ 1 rms eel With a large f . o· ' w Ic 1 can be folde l l'l an, and is coloured bl bl 1 c up 1 re a 1 d .d ue, ac r, and reel· b t th sp on I colours are exh'b't d 1 . ' u ese season. The female d I 1 e on y durmg the pairing-of this appenclag;. I~e:h~o~pos~oss ~Yen a rudiment ing to M:r. Austen th tl . nobs cnstatellus, accord-l ' e Hoat-pouch 1 · 1 · b · r ec mar1led with yell . ' w nc 1 IS nght mental condition in ~:' If~ prel. ent, though in a rudi-th l . ' o ema e lO'ai . . <> cr rzards both sexe · L o' n, In certa1n l · ' s are equally,. ll ·., . t. 1l'oat-pouches. IJer .o , as ' \ e provruecl w1th m so many previous cases ·we see with species be~ longing to the same group the same character con~ fin ed to the males, or more Jargely developed in tho males than in the females or equally developed j~ both sexes. The little li- Fig. 33. Sltan.t minor. J\lule, with tbc gular d f pouch expanded (from GUnther's 'Rep- .zar so the genus Drac tiles oflndia.'). l. h . 0 w uc ghde through the a' ir on th .. ·'b . chutes, an<l which in the b en u -~upported para-description are fu . .eauty of thOir colours baffie throat, "liiw the r~Isthtlecl wfrth sl~inny appendages to the t.. "a es o galhnaccous birds " 1,1 'Uecome erected , h th . . · wse • L 1 v en e ammalrs excited Th 111 uot 1 sexes but are best d 1 . . oy occur arriveu at m~turit . eve oped m tho malo when is sometimes t . y, at '~hwh nge the middle appcndaO'e species 1'1~ . wwle as ong as the head. Most of the J ~ew1se 1ave a low . t . neck. ancl th' . Cies nmnmg alOJw the ' 1s 1s much more c1 1 1 · 0 grown males tl . h eve opec m the full- ' 1an m t e females or young males.Go "" All these statements n.ud . . :and Drnco, as well as the foll q~IO~a2ons, .m regard to Copbotis, ilnun VOL. II. owm, acts m regarll to Ccmtophorn, t<rC . D |