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CDrraSurg nf Batumi 



costershire, to the coast of Yorkshire. The 

 lias of Germany and France also contains 

 them. 



Mr. Pearce found, within a specimen of 

 the Ichthyosaurus, what he thinks may have 

 been an embryo ; and although the Ichthyo- 

 saurus, by analogy, might have been sup- 

 posed to be oviparous in its generation, yet 

 Dr. Buckland and Professor Owen think 

 there is no reason why it should not have 

 been viviparous ; and from the evidence of 

 Mr. Pearce's specimen it appears fair to sup- 

 pose that they really were so. The collec- 

 tion of remains of Ichthyosauri in the Bri- 

 tish Museum is very perfect and great : and 



I with the allied Plesiosauri forms quite a 

 feature in the room devoted to their exhi- 



I bition. 



i ICTERIA, or CHATTERING FLY- 

 . CATCHER. (Icteria virulis.) This bird 

 abounds in most parts of North America 

 ! during the summer months, and is remark- 

 able both for its colouring and its habits. 

 ! It is about six inches in length : nearly the 

 i whole of the upper parts of its body are of a 

 i rich deep olive green, the tips of the wings 

 I excepted, which are of a dusky brown : the 

 ! throat, breast, and sides of the body are of a 

 : bright yellow ; the belly and vent white ; the 

 I forehead pale ash ; from the nostrils a line of 

 | white extends to the upper part of the eyes, 

 I which it nearly surrounds ; another white 

 I spot is situated at the base of the under man- 

 I dible : beak strong and black ; legs and feet 

 pale blue. It has the faculty of mimicking 

 almost any noise that it hears, which it will 

 repeat during the whole night if the weather 

 be fine. Its favourite residence is in close 

 hazel or bramble thickets, and its nest is 

 composed of dry leaves with layers of grape 

 vine bark, lined with fibrous roots and dry 

 grass. The female lays four flesh-coloured 

 i eggs, sprinkled with brown and dull red 

 | spots. 



i IGUANA. A gemis of Reptiles of which 

 | there are several species ; the genus includ- 

 ing several of large dimensions, common 

 I in the tropical parts of America, some of 

 i which feed on vegetable substances, and 

 ; are esteemed delicious food ; while there are 



others which appear to be omnivorous. 

 They are thus characterized by Cuvier : 



body 

 scalei 



and tail covered with small imbricated 

 scales : the ridge of the back garnished with 

 a row of spines, or rather of elevated, com- 

 pressed, and pointed scales ; under the throat 

 a depressed and depending dewlap, the edge 

 of which is attached to a cartilaginous 



appendage of the hyoid bone. Their t lighs 

 are provided with a similar arrangement of 

 porous tubercles with the true lizards, and 

 their head is covered with scaly plates. 

 Each jaw is furnished with a row of com- 

 pressed triangular teeth, having their cutting 

 edges serrated : there are also two small 

 rows on the posterior part of the palate. 

 They live for the most part on trees, but 

 sometimes take to the water, and swim 

 with ease. They attain a great size, being 

 sometimes found five feet in length, though 

 they are much more often from two to three: 

 their upper parts are bluish-green,and some- 

 times slate colour ; the under parts yellow- 

 ish-greeii ; in general, on the sides of the 

 body are brown stripes or zigzags edged with 

 yellow ; and the tail is surrounded with 

 large brown or yellow rings. The Common 

 Iguanas (If/uana tuberculatu) are eagerly 

 sought, especially in the spring, being es- 

 teemed a great delicacy. They are caught 

 by means of a noose attached to the end of 

 a stick : for the animal, though formidable 

 in appearance, is timid and defenceless. It 

 is very active ; but when it has taken refuge 

 in a tree, it appears to depend on the secu- 

 rity of its situation, and never offers to stir 

 unless roused ; hence it is easily taken. 

 The female deposits her eggs, which are 

 about the size of a pigeon's egg, in the sand, 

 where they are left to be hatched by the 

 genial warmth of the sun. 



IGUANIDJE. The family of Saurians, 

 or lizard-like reptiles, of which the animal 

 just described is the type, and of which there 

 are several sub-genera: descriptions of which 

 are given in Mr. Gray's elaborate work, the 

 Catalogue of Lizards in the British Museum. 

 [See LIZAKD.] 



IGUANODON. The name given to an 

 extinct gigantic reptile, closely resembling 

 the Iguana in osseous structure, whose re- 

 mains were discovered by Dr. Mantell in 

 the wealden formation of the South of 

 England, in the localities of Purbeck, the 

 Isle of Wight, and Maidstone. From its 

 dentition there seems to be no doubt that 

 it was herbivorous ; the form of the teeth, 

 considered with relation to the demands 

 made by the habits of the animal, being well 

 adapted for cropping tough vegetable food, 

 such as the Clathraria and similar plants 

 which are found buried with the Iguanodon. 

 From the proportions which the bones of 

 the Iguanodon bear to those of the Iguana, 

 this t xtinct monster is calculated to have 

 been 70 feet in length from the snout to the 

 end of the tail ; the length of the tail alone 

 52^ feet, and the circumference of the body 

 14i feet. The thigh bone of the full-sized 

 Iguanodon is twenty times the size of that 

 of the Iguana ; and on the snout of this pro- 

 digious reptile was a short but strong horn : 

 its whole appearance, indeed, must have 

 realized the wildest poetical fictions of the 

 dragons of old. In the British Museum are 

 contained all the specimens of Iguanodon 

 obtained by Dr. Mantell ; and a comparison 

 of the teeth and bones, with those of its 

 recent comparatively Lilliputian analogue, 

 is a most interesting and curious study. 



