127 



group from wliicli the latter have spninij. That tliis order is not tliat unknown 

 type is clear; !)ut the indication of alKnity to it is equally unmistakable. 



Restoration. 



The proportions and appearance of the Tythonomorpha can be determined 

 from the remains which have been jjrocured. The body-cavity is more 

 elongate than in any group of lizards and sauriahs, excepting the Amphis- 

 h(enia, l)ut not so long as in serpents. 'J'he tail is excessively long and 

 flattened. The head is also long — in some genera, as Clidastes, very slender, 

 and always flat, with the eyes nearly vertical. There is no distinction between 

 neck and body, but a contraction behind the head. The limbs arc very small 

 for the size of the animal, forming broad paddles, with but little peduncle; 

 the hinder limbs well behind tlie ribs, and often smaller than the anterior. 

 The general effect of the more slender of llicsc animals was that of gigantic 

 eels, or some of the snakclike lizards of the present lime, so that they are 

 veritable sea-serpents of the Cretaceous ocean, and would doubtless be 

 described as such were any perchance to be found to be still in existence in 

 the depths of modern oceans. 



Several peculiarities affecting the appearance of these animals may be 

 derived from the peculiar articulation of the lower jaws. The position 

 of these articulations in advance of the pharynx indicates a baggy extension 

 of the gular walls, to permit the passage of large bodies between the jaws to 

 the (Esophagus. This had, perhaps, the appearance of the posterior part 

 of the pouch of the pelican. This arrangement necessarily requires that the 

 larynx should be, as in the serpents, in the middle or anterior part of the 

 mouth ; for, as in those animals, the delay involved in deglutition would cau.sc 

 suffocation were the glottis immediately below the descending mass. T'his 

 structure requires another, namely, the anterior position of the tongue ; and 

 this organ, unless very small, would have to be received into a sheath beneath 

 tlie larynx and opening anterior to it. Ensheathcd tongues, among reptiles, 

 tend to become cylindric in proportion to the completeness of the sheathing, 

 for obvious mechanical reasons. It is almost certain that the I'ytliononwrplia 

 had tongues of this kind ; for their nearest living allies on l)()tli sides iiave 

 them, viz, the serpents and the varaiiian or thecagloss lizards. These have 

 the tongue cylindric, ensheatlied, and forked at tlu^ cud, and project it as a 

 delicate tactile organ. 



