AC A NT HO PTERYGII. 



13 



in proportion to the diameter, though the whole ani- 

 mal is of small size. The head is obtuse, covered in 

 part with nine or ten scaly-guard-plates, and the 

 plates round the eyes are partially raised or erected, 

 so as to give a faint resemblance of a crest. The 

 upper part of the body is covered by imbricated 

 scales of a rhomboidal form, and the lower part par- 

 ticularly by simple plates as already mentioned. Be- 

 sides the poison fangs, the jaws are armed each with 

 a double row of small reserved teeth, to assist in the 

 process of deglutition ; and from the extent of the 

 gape it may be at least supposed that the prey which 

 they swallow is large in proportion to their size. 



In New Holland, the only country where they 

 have been ascertained to exist, they live in holes 

 at the roots of trees or otherwise in concealment, and 

 kill lizards and other small animals by poisoning. 

 The New Holland species has been designated 

 llrownii, after Brown the botanist. The body is 

 coaly black, with some white on the upper lip. The 

 tail is flattened, and its junction with the body is indi- 

 cated by a diminution of the diameter. It is under- 

 stood to be the most poisonous serpent in Australia; 

 and as such, we may naturally suppose that exagge- 

 rated stories respecting it will be circulated. Another 

 species, of which the native habit is not known, has 

 been called ccrastinus, from its resemblance to the 

 crested viper, or horned viper of Egypt and Nubia. 

 It is greyish above, and brownish-yellow on the under 

 part, with black spots on the edges of the abdominal 

 plates. 



AC ANTHOPTERYGII ; Spinous-finned Fishes. 

 A very numerous order of bony fishes, or of those 

 that have their skeletons with the greatest proportion 

 of earthy salts in their composition, and, therefore, 

 the hardest that are met with among the fishes, though 

 inferior in that respect to the bones of the mammalia 

 and of birds. Their bones are, in the recent state, 

 semi-transparent ; they are more or less flexible ; and 

 they arc without the ordinary cells and tubes in the 

 internal joint, which are filled with marrow or oil in the 

 bones of the mammalia, which answer the purposes of 

 air-tubes in those of birds. 



Their skeletons consist of the bones of the head, 

 the spine, and its ribs and branches, and other small 

 bones to which the fins are articulated, and which are 

 either embedded in the muscles, as the shoulder-bones 

 are in the mammalia, or articulated to the processes of 

 the spine by elastic tendons. As the bones are most 

 perfectly developed in the division under consider- 

 ation, this seems the proper place to notice the difference 

 between them and the bones of the other vertebrated 

 animals. The head consists of a great number of 

 bones, as many as 70 or 80 in some species ; but they 

 adhere to each other, and the sutures, or innumerable 

 joinings, become obliterated. The bones of the head 

 are altogether, in general, large in size ; but the cavity 

 for the brain is small. The teeth, except in a few spe- 

 cies, are instruments of prehension rather than of mas- 

 tication ; they are, in general, very numerous and 

 small, and the palate and partially the tongue are 

 sometimes beset with them as well as the jaw. The 

 head is united to the spinal column by a single tu- 

 bercle, but the joint admits of little motion. There 

 are never many of the vertebrae of the spinal columns 

 cervical or tending to form a neck, and in most of the 

 divisions there are none. The section of the vertebrae 

 is sometimes circular, sometimes angular, and sometimes 

 compressed laterally. The dorsal and caudal parts of 



the spine consist of a vast number of vertebrae, varying 

 in different species and tapering towards the tail ; the 

 last one being always compressed laterally, and ge- 

 nerally rounded, particularly where the small bones 

 of the caudal fin are articulated. 



The form of the vertebrae and the mode of their ar- 

 ticulation, as compared with those of the other three 

 orders of vertebrated animals, are worthy of notice, as 

 indicating a greater simplicity of purpose than in that 

 of the fishes. In them the spine is nothing more than a 

 flexible rod. Each vertebra is a short cylinder or prism, 

 according to the form of the section, terminating in a 

 conical cup at each end. The interior of these cups 

 is marked by concentric rings, said (but not proved) 

 to indicate by their number the years that the fish has 

 lived. The cylinders usually widen a little towards the 

 mouths of the cups, which are slightly turned over 

 or rounded. These cups are, in the living state, com- 

 pletely filled by cartilaginous fibres, softest toward 

 the centre, where, from the form of the cups, they are 

 also largest ; they allow of free motion laterally, though 

 not to any great extent in the single articulation ; 

 and the whole is at the same time highly elastic. The 

 chief difference between the bony and cartilaginous 

 fishes in this part of their structure is, that in the 

 latter the column has little distinction of vertebrae, 

 but is equally flexible through its whole length. 



The dorsal part of the column, or that which an- 

 swers to the spine of the trunk in the mammalia, is 

 without spinous processes on the under side, but has 

 them on the upper, and also obliquely and laterally, 

 the ribs being articulated to the latter. All the bony 

 fishes have ribs, sometimes forked, sometimes double, 

 sometimes compressed, and sometimes in the shape 

 of bristles ; but in the cartilaginous fishes they are 

 wanting. The caudal vertebra? have spinous processes 

 both on the upper and the under side, which become 

 smaller towards the termination, according to the shape 

 of the fish. The clavicles support the sides of the 

 body behind the gill-openings ; and the pectoral fins 

 may be considered as having some resemblance to the 

 anterior extremities in the mammalia and the wings of 

 birds ; but the bones answering to the pelvis are very 

 obscure. 



The principal muscles in the bodies of these, and, 

 indeed, of all fishes, are placed on the sides of the 

 spine, and supported by the processes. They are 

 formed in layers, placed in curves with their convexity 

 toward the head. In this division they appear to 

 contain more albumen and less gelatine than in the 

 cartilaginous fishes, and even less than in those which 

 have soft fins. The spinous fins have also more mo- 

 tion than those with soft rays, and especially than the 

 fleshy ones ; but so little is known of the habits of 

 the animals that no very certain conclusion can be 

 arrived at. The muscular action in swimming consists 

 in bending them to each side alternately, accompa- 

 nied by expansions of the rays of the caudal fin, re- 

 sembling the opening of a fan ; and in those fishes that 

 have large scales the posterior margins of these hold 

 on upon the convex side when the body is bent, and 

 thus tend to steady the action and prevent recoil. 



The brain forms a smaller portion of the whole 

 nervous mass than in the warm-blooded animals ; and 

 as the spinal column is in proportion to the body, not 

 to the brain, we may naturally conclude that the ener- 

 gy of the senses, taken on the whole, is inferior to that 

 of motion and digestion. They do not appear to 

 feel much pain from wounds in the flesh ; but in some 



