the vent, which is of nearly equal diameter for its 

 whole length, is capable of very little flexure ; and 

 the sudden diminution in thickness of the tail after 

 this enables that organ to move from its base with 

 much more freedom and less disturbance of the 

 anterior part of the body, than if the taper were more 

 gradual. This allows a sort of repose to that portion 

 of the animal which contains the vital organs, and also 

 which bears the eggs, whether in the interior of the 

 female, or on the exterior of the male, while the tail 

 is at perfect freedom to impel the body through the 

 water. Thus, comparatively finless as it is, this spe- 

 cies appears to be better adapted for free swimming 

 in the under-sea, than those members of the family 

 which are the most amply provided with fins, and 

 which, on a cursory view, we should be apt to regard 

 as the best swimmers. 



Snake Pipe-fish (S. ophidion). This is the most 

 snake-like in its form of the whole race. The tubu- 

 lar portion is long and slender, the head very small, 

 the body also small, but of uniform thickness to the 

 vent ; the tail is very long and slender, and tapers to 

 a very fine point, or rather it tapers till it becomes 

 exceedingly slender, and then the tip of it is slightly 

 enlarged and compressed. Slenderness is indeed the 

 remarkable character of this fish ; for in a specimen 

 a foot long no part is thicker than an ordinary goose- 

 quill. The tail behind the dorsal fins is considerably 

 longer than the body and head ; and as about a 

 fourth of the fin is in rear of the vent, that portion 

 also must be considered as belonging to the tail. 

 The body appears to be much less angular than in 

 most of the other species.by the longitudinal rays being 

 nearly obliterated, and the junctions of the plates on 

 the sides of the body are also Very indistinct. So 

 far as the vestiges of the ridges can be traced, the 

 body is octangular in the section, with one ridge on 

 the back, another on the belly, and three upon each 

 side. The colour is a pretty uniform olive green, 

 without any cross bars or mottlings. The irides of 

 the eyes, which are rather prominent, are red, and 

 the pupils black. 



There is no vestige of a pouch on either the fe- 

 male or the male, but the latter has depressions on 

 the abdomen for receiving the eggs, which do not 

 appear to be matured till the early part of the au- 

 tumn. This appears to be a discursive species as 

 well as the preceding; and though specimens have 

 been taken near the land, it has been in the free 

 water, and where that water had a current. It has 

 been mentioned as occurring both in the northern 

 and the southern seas of Britain, although most fre- 

 quently in the latter ; but every where it is compa- 

 ratively a rare species. Twelve or thirteen inches is 

 the greatest length of any that have been described ; 

 and it is curious how so light and slender a thing can 

 endure so well as it appears to do the violence of our 

 seas in their most turbulent state. The probability 

 is, that these, like all the more slender fishes, 

 retire to a depth below the vibration of the waves 

 in all cases of storms, for they are seen swimming 

 over the surface only when the weather is fine and 

 the sea tranquil. 



Wotm-thaped Pipe-fish (S. lumbriciformis). This 

 is the smallest of all the British Syngnathi ; and 

 though it agrees with the rest of the section in all its 

 more general and essential characters, its appearance 

 and manners are somewhat different. It is seldom 

 more than between five and six inches in length, and 



76? 



smaller in r the thickest part of the body than an or- 

 dinary earth worm. The tubular part of the mouth 

 is shorter than in the others, and curves upward at 

 the extremity. The head is rather large, and the 

 thickest part of the body is near the head, from which 

 it tapers uniformly to the point of the tail. The 

 head, from the point of the snout to the posterior 

 edge of the operculum, is one-twelfth of the whole 

 length ; the head and body to the vent make only a 

 third of the length, leaving two-thirds to the tail ; 

 three-fourths of the dorsal fin are on the tail, and 

 only the first fourth on the body. There are about 

 nineteen plates on the side in front of the vent, and 

 as many as fifty on the tail. These plates are but 

 little conspicuous ; and the longitudinal lines are 

 almost wholly obliterated, so that the section of the 

 body is nearly circular ; the surface is also smooth ; 

 the colour is dark olive green. This species is a 

 shore fish, and not a pelagic one. Its habits are 

 lurking, and it is usually found under stones, It is 

 met with on various parts of the coast, and even in 

 the northern islands : and in some places of the south 

 it is reckoned very common. 



HIPPOCAMPUS Sea-horse. The fishes of this ge- 

 nus are even more singular than the Syngnathi, both 

 in their appearance and their habits. They have 

 the body much compressed and very considerably 

 deeper than the tail, to the thickness of which the 

 posterior part of the body is reduced by a very rapid 

 curve, which, for a reason afterwards to be explained, 

 is much more conspicuous in the female than in the 

 male. The depth of the body is also much contracted 

 toward the head, which, with the enlarged operculum 

 and the elevated angular plates on the head behind 

 the eyes, gives the fish the appearance of having a 

 true neck as in mammalia and birds. This part is 

 also much more flexible than in any other fish, so that 

 the head can be moved upon the body, and thus be- 

 come, by means of its angular and spinous projections, 

 an instrument of prehension, by the help of which the 

 fish can climb. This flexible portion is not a neck, 

 however, but a part of the body, for the pectoral fins 

 are in advance of it, and when they are exerted they 

 have something the appearance of ears. The tubular 

 part of the mouth is very slightly bent upwards, and 

 the gape oblique and very small. The eyes are pro- 

 minent, and the widest part of the head is across 

 them, the crest behind being compressed, so that 

 when seen in front it has the appearance of an orna- 

 mental crest set on the head rather than belonging- 

 to it. There are two spiny elevations immediately 

 over the eyes, and the pectoral fins look like ears 

 placed immediately behind. The general profile of 

 the head is of a triangular shape, and in the female 

 the crest toward the hind head rises higher than in 

 the male. The body and tail are angular, with pro- 

 minent longitudinal ridges, which are crossed by other 

 ridges at the junctions of the plates, extending round 

 the body, and forming little projecting knobs where 

 they cross the longitudinal ones. Both sexes have 

 dorsal fins as well as pectorals, the dorsal being 

 wholly or nearly in advance of the vent ; the female 

 only has a small anal fin, and neither have any ven- 

 tral or caudal. Indeed the tail is more completely 

 finless in them than in the Syngnathi which have no 

 caudal ; for these have the dorsal in part upon the 

 base of the tail. The tail is prehensile, and can twine 

 firmly round the stems of seaweed, or other small 

 substances, its hold being rendered more firm by the 



