VOL. XIII.] PHILOSOPHICAL TRANSACTIONS. 573 



presented in our figure; only where some other bones were joined to them, as 

 forwards over the nostrils, were 2 small bones, (cc) to which were fastened 

 the cartilages (d) or rather bones which divide the nose. The other bones 

 seemed admirably contrived for the great extension and widening of the maxillae, 

 which seems a great provision of nature; for since it must swallow all things 

 whole, and its head is but small, without this most mechanical contrivance it 

 were impossible to do it. The upper jaw forward was joined to the bone that 

 receives the poisonous fang, and which had a large cavity in it, which opened 

 outward, and was thought to be the foramen of the ear, (fig. 5, b) but inwards 

 we observed no perforation for a nerve, unless there might be one that comes 

 to it under that bone (fig. 6, ee) which conjoins it to the cranium. This arti- 

 culation seems advantageous, both for the motion of the fang, which lies some- 

 times couched, sometimes erected, as the jaw too; but its principal and most 

 remarkable advantage for swallowing large bodies, is the curious articulation of 

 the maxillae backwards to the cranium by 2 bones, which from their use (since 

 we know no name to distinguish them by) we shall call maxillarum dilatores. 

 Their shape, size, and aptness for this motion, will readily enough be con- 

 ceived by the eye in observing the figure (fig. 6, no). For the lower jaw being 

 not conjoined at the mentum, as is usual in other animals, but parted at a good 

 distance; upon the receiving a large body, as the membrane here to which they 

 are fastened easily extends, so by lifting up, as also by bringing these two bones 

 more to a straight line, it must needs considerably widen the rictus of the 

 mouth, and" for this cause too they are made 2, not 1, for performing this mo- 

 tion more easily. This articulation (m) of the dilatores (which is very curious) 

 with the upper and lower jaw, makes those protuberances of the head, which 

 we likened to that of a bearded arrow, as does Hor. lib. iii. Od. xxvii. 



The lower jaw of each side was composed of 2 bones, as appears in the fi- 

 gure, but firmly conjoined. The fore bone was for receiving the small teeth, 

 the hinder towards the articulation gre\v broad, as likewise did the bone of the 

 upper jaw answerable to this place in the lower. But this upper jaw towards 

 the poisonous fang divided into 2 bones, one was fastened to the bone of the 

 poisonous fang outwards, the other, which received the small teeth, was in- 

 serted into the same bone more inwards. 



The vertebrae, according to the whole figure of the body, were smallest to- 

 wards both extremes, and largest in the middle. From the neck to the anus 

 there were as many observed scales on the belly, viz. l68, but from the anus 

 to the setting on of the rattle 29 more in number than the scales. The former 

 vertebrae had a flat upright spine (fig. 8, a) towards the back, and a slender 

 round oblique descending one (b) inwards to the belly. To each vertebra, be- 



