

8AURIA. 



SAURIA. 



thaw vertebras U 22, there being no lumbar vertebra ; for there are 

 rib* from the neck to the pelvis amounting to 27 pain, including the 

 6 cervical, but the first and the last of these rib* are very small The 

 first pair of rib* i* attached to the third cervical vertebra. The first 

 five pain are not united by mean* of cartilage* to the sternum, and on 

 this circumstance Cuvier relies to distinguish the cervical vertebra), 

 which, adding the atlas and dentata (these last having no ribs), makes 

 their number 7, as in the Crocodile* and Mammals generally. The 

 first three dorsal rib* only are attached to the sternum ; the 17 suc- 

 ceeding one* are false rib*. Cuvier remarks that the total absence of 

 lumbar vertebra) appear* to him a general rule in the family of 

 Saurian*. 



There are two sacral vertebra) in the Monitor. Tho first has, hi 

 lieu of a small tubercle, a Urge apophysis, convex externally, and pre- 

 senting to the oesa ilii an articular surface notched behind, and of a 

 horse-shoe shape. The second has also a Urge apophysis, but simply 

 widened and flattened horizontally. The caudal vertebra) after the 

 eighth are very numerous (70, 80, and more ) ; they may be easily 

 recognised by their spiuous and transverse apophyses or processes, 

 which are long and narrow, and their articular apophyses or pro- 

 cesses, which are nearly vertical, the anterior looking inwards, the 

 posterior outward* ; and also by having on their lower surface, 

 towards the hinder part, two small tubercles for supporting the 

 chevron bone, which occupies the place of a lower spinous process. 

 These two small tubercles are placed more forward in the Monitors 

 than in the other sub-genera ; for in the Utter they touch the pos- 

 terior articulation, so that the chevron bone appears to be attached to 

 the vertebra. All the caudal vertebra) of the Monitor have, like the 

 preceding, the anterior surface concave and the posterior convex, and 

 they go on diminishing in proportion as they approach the extremity 

 of the tail, their prominences finishing by being reduced almost to 

 nothing. 



The cervical vertebra), determined by the anterior false ribs, are 

 eight in number, that is to say, there are six pairs of these false ribs, 

 and this number is found in many other sub-genera, particularly in 

 the Jyuana, the Basilisks, the Lizards, the Geckos, the Anolides, the 

 Agamce, and the Stelliones. The last two, and sometimes the lost 

 three ribs, though they do not reach to the sternum, yet are placed 

 under the shoulder, and concur in the formation of the thorax, so 

 that the vertebra) which support them may be placed among the 

 dorsal, which would reduce to five the number of vertebra) really 

 belonging to the neck. In the ordinary Lizards, the Skinks, and 

 slightly in the Anolides and the Geckos, the cervical ribs attached to 

 the fourth, fifth, and sixth vertebrae are singularly compressed and 

 widened at their free extremity. The differences which characterise 

 the vertebra) of the different sub-genera, independently of what Cuvier 

 had already remarked as to the position of the tubercles of the 

 caudal vertebra) for the chevron bones, especially consist, he informs 

 us, in the respective length and stoutness of their bodies, and the 

 respective length and width of their apophyses. Tho Iguana has the 

 spinous processes of its dorsal vertebra- less lofty, and, cut, as it were, 

 more obliquely. The bodies of it* caudal vertebra) are more elon- 

 gated, so that with a lens number they form a greater length. Their 

 spinous processes decrease more rapidly. The Basilisks have very 

 nearly the characters of tho Jyuana, but their dorsal spinous pro- 

 cesses are high and narrow, as well as those of a part of their tail. 

 The Agamahvie also the dorsal spinous processes high, straight, and 

 narrow; but the Stellios have them low. In the Lizards they ore 

 tolerably high, but directed somewhat obliquely backwards. 



The rib* of the Saurians are (lender, round, and the anterior ones 

 only have the costal head slightly enlarged and compressed. Cuvier 

 had never seen any of them with a division at their upper extremity 

 into a head and tubercle. The anterior rib* of the Monitors are a 

 little more widened in the upper part* than those of other Saurians. 

 Instead of those (imply ventral rib* which arc wen in the Crocodile, 

 many sub-genera, especially in the J'olychri, Anolises, and Chameleons, 

 after the rib* which are united to the sternum, have others which 

 unite mutually with their corresponding rib, and thus surround the 

 abdomen with entire circle*. 



The sternum of the Saurians, taken together with their shoulder, 

 forms, says Cuvier, a kind of cuirass for the heart and Urge blood- 

 vessel*. It i* more complicated than in the Crocodile*, and formed 

 upon a plan very different from that of the Tortoises. It consist* 

 essentially of a long narrow depressed bone, which gives off anteriorly 

 two branches directed to each side, more or less recurrent, according 

 to the species, and between which its point passes sometimes to 

 advance more forward under the neck. This bone penetrate* with it* 

 posterior part into a cartilaginous plate of a rhomboidal *hape, which 

 ba* two side* forward and two backward, and which often shows trace* 

 of longitudinal division into two portions. IU interior side* are 

 continued with the edge* of the .'anterior part of the bone, but in 

 divaricating to the right and left They are sometimes ossified, par- 

 ticularly their edge, which has a groove, in order to give support, like 

 mortise, to the sternal edge of the oUvicuUr bone. The posterior 

 sides of the rhomboidal cartilage serve for the insertion of the false 

 ribs. So far there is no great difference in this part of the organi- 

 sation from that of the Crocodile, except in the anterior branches ol 

 the elongated bonr, which give it the form of a T, of an arrow, or of a 



cross, according to the species; but a more considerable difference is 

 apparent in the development of the coracoid bone, and in the constant 

 iresenoe of a clavicle more or less large. The coracoid bone, ai in tho 

 Crocodiles, tho Tortoises, and all the animals which have a true arm, 

 concurs in the formation of the glenoid cavity, and in the true 

 Saurian* affords nearly half of it Widening more than the bony 

 plate of the shoulder-blade, it proceed* to articulate itself to the 

 sternal rhomboid by a wide edge, which take* the form of the blade of 

 an axe ; but its peculiarity consists in the giving off one or two apo- 

 physes, by means of which it supports a great cartilaginous arch which 

 piroo* on the slender and advanced bone of the sternum, and lies 

 across that of the coracoid bone of the other side. 



The scapula, or shoulder-blade, produce* the other part of the 

 glenoid facet ; it goes on, as odinarily, enlarging on the side of the 

 thorax and towards the back ; and at about a third or the middlo of 

 its length stops short, but is continued in a single portion, which ia 

 generally cartilaginous, or which, when it is ossified, which frequently 

 happens, becomes so in a different manner, and with another texture, 

 like the cartilage adhering to the coracoid bone. In the case of ossi- 

 fication, the scapula is always divided into two bones. 



The clavicle rests ou one side against the slender bone of the 

 sternum, or against its lateral branch, and often also it reaches to the 

 opposite clavicle ; on tho other side it proceeds to rest against the 

 anterior edge of the scapula, either against the osseous portion or that 

 which remains longer cartilaginous, and which often presents a 

 tubercle or small crest for its reception. Sometimes the bony scapula 

 gives off an apophysis which goes to sustain the body of the clavicle, 

 but this is all that it presents as a slight resemblance to an acromion : 

 the tubercle of the cartilaginous part resembles that process much more. 



The pelvis of the Saurians (Cuvier takes the Monitor as the 

 example) is composed of three bones, which concur, as in the vivi- 

 parous quadrupeds, to compose the cotyloid fossa. Its upper part in 

 formed by the ossa ilii ; its neck is wide and short ; its spinal part, 

 instead of being directed forwards, as in the viviparous quadrupeds, 

 or of being rounded as in the Crocodile, runs obliquely backwards in 

 the form of a narrow band, and has only a small point in front The 

 pubis and the ischium are each united to its opposite in the median 

 inferior line ; but the pubis is not joined to the ischium, and the two 

 oval holes are only separated by a ligament Their neck U wide, 

 short, and flat That of the pubis ia pierced with a rather large hole, 

 and its anterior border produces a point which is recurved downwards 

 and outwards. Cuvier adds that the pelvis in the different sub-genera 

 is especially distinguished by the symphysis of the pubis, which is 

 formed by a rather wide truncature in the Monitors, and even slightly 

 in tho Sauvegardes ; but only by a narrow point in the majority of 

 others. The Chameleon differs from all the others in its narrow ossa 

 ilii, which proceed perpendicularly in widening slightly to attach 

 themselves to the spine. These ossa ilii are still further distinguished 

 by a triangular cartilage, analogous to that of the shoulder-blade. 

 The symphysis of its pubis is formed by a truncature, and there is no 

 lateral point. 



The cylindrical bones of the Saurians exhibit the following cha- 

 racters : The humerus agrees very much in form with that of liirdn. 

 Its upper head is compressed, to answer to the hollow fosset which 

 the shoulder-blade and coracoid bone together present to it Its 

 lower pulley is formed of two projecting rotatory portions, entirely 

 rounded, the external of which is the least developed. The internal 

 condylo also projects more than the external, the deltoid crest pro- 

 duces an angle more projecting forwards, and its posterior tuborosity 

 ia less hooked. In these two last respects it more resembles that of 

 the Crocodile ; but it has in general all its articular surfaces much 

 better defined. But tho humerus of a lizard may always be distin- 

 guished from that of a bird, because the former is not hollow, nor 

 pierced with holes for the admission of air into its interior. The ulna 

 of tho Saurians is compressed and trenchant on its radial edge. Its 

 sigmoid facet is oval, and it* olecranon projects but little ; its carpian 

 head U also oval and uniformly convex. The radius is delicate ; it* 

 upper head is oval and concave ; it* lower, which is slightly convex, 

 presents to the first bone of the carpus a rounded tubercle and a fosset 

 of a crescent-shape. The femur in its upper part resembles that of 

 the Crocodile much more than that of birds, and this has reference to 

 the direction of the foot in reptiles. Its upper head is compressed 

 and curved in front, and has its trochanter on the tibiol side placed 

 nearer to the head of the bone than in the Crocodile, much more 

 projecting, and of a compressed form. The lower head of the femur, 

 on the contrary, much resembles that of birds, especially in the small 

 hollow on the peroneal side for the head of the fibula. The patella U 

 very small, often hardly visible, Tho leg is always composed of two 

 bone*, of which the tibia is the largest Its upper head is triangular, 

 as ordinarily ; its lower is transversely oblong and flat The fibula of 

 the Monitors is flattened and widened below, where it unites to the 

 tarsus by a narrow line. In the Iguanas and the greater part of the 

 other genera it is nearly of a size throughout, slender, with its upper 

 head compressed, and its lower demi-oval and slightly oblique. 



The bones of the fore and hind feet in the Saurmns consist of a 

 carpus composed of nine bones, like that of the Tortoises, and Cm-j.-r 

 remarks that its composition may equally be compared to the Siniada. 

 In the first row ore a radial bone, a cubital bone (rather Urge), and a 



