A M E T H Y S T E A A M M O D Y T E S. 



colour, and in Its pure state of nearly the same degree 

 of hardness and general chemical properties as the 

 oriental topaz and ruby. It is usually divided into 

 two varieties, the common amethyst and the thick 

 fibrous amethyst. The latter is found in agate veins, 

 and is generally accompanied by the preceding sub- 

 species. 



The common amethyst, which is by far the most 

 interesting form of this mineral, was well known to 

 the ancients. Its form is usually that of a six-sided 

 pyramid, and at other times that of a six-sided prism, 

 surmounted with the same number of planes. 



The common amethyst occurs in veins and cavities 

 in the secondary or floetz greenstone of Fifeshire j it 

 is also found at Montrose, and in the Hill of Kinnoul 

 near. Perth. Upon the continent of Europe it occurs 

 in great abundance, and also in North and South 

 America. See CORUNDUM. 



AMETHYSTEA (Willdenow). A single species 

 of a pretty little blue flowering annual, a native of 

 Siberia. It belongs to the natural order Labiatce ; 

 and is not cultivated in gardens so much as it deserves 

 to be. 



AM I A. A genus of soft-finned fishes with ab- 

 dominal fins, belonging to the natural family of the 

 herrings, and to that division of them which inhabit 

 the fresh waters, and which are most abundant in 

 America. Their bodies are covered with large scales 

 resembling those of carp ; but the head has no scales, 

 and is armed with hard bony plates. The air-bag is 

 cellular. They have the teeth strong and conical, 

 and the point of the under jaw is fortified by a buck- 

 ler of bony substance. The nostrils are tubular, the 

 dorsal-fin is much produced, and the anal one is 

 stout. There is only one species known (Amia calvci) ; 

 it is an inhabitant of the rivers of Carolina, and 

 understood to feed upon crabs. The flesh is not 

 esteemed as food. 



AM I A. An ichthyolitc, figured by Cuvier, and 

 referred by him to this genus of fishes, is described by 

 Blainville as found in a block of gypsum. It is 

 twelve inches long and four high ; the head being 

 equal to one-third of the length. Another species is 

 described by Mantell, in his " Geology of the South- 

 cast of England," as found in the chalk near Lewes ; 

 it is distinguished from the former by the angular 

 shape of the head, the anterior dorsal fin having spi- 

 nous rays, and by the scales being of a scabrous 

 structure ; he has named it A. Lcwcsiensis. Among 

 other curious particulars mentioned respecting this 

 fossil, he states that several specimens not only exhibit 

 the tongue and its papillae in good preservation, but 

 even the air bladder, which appears of an elongated 

 oval form, situated in the abdomen, immediately under 

 the spine ; thus proving that parts of the most deli- 

 cate structure may occasionally be found in good 

 preservation in a mineralised state. 



AMMOC./ETES. A singular genus of cartila- 

 ginous fishes, of which the bones arc so soft and 

 flexible that they hardly deserve the name of bone. 



There is only one species, the pride, or " stone- 

 grig" (A. bronchialis), a native of some of the rivers 

 of England, and especially those of Oxfordshire, but 

 even there it is riot very abundant, it lives in the 

 tough and clayey rnud, for which the streams in that 

 part of England are remarkable, and it has many o 

 the habits of a worm. When full grown it is about 

 eight inches in length, and of the thickness of a goose- 

 quill; and its body i* annuljttcd or marked with 



rings, which add to its worm-like appearance. In 

 external appearance it is a miniature of the lamprey ; 

 )ut the maxillary ring or sucker, and, indeed, the 

 iiouth altogether, is without teeth, having instead 

 small reflected barbs or bristles, on the palate and 

 he entering of the gullet. When it breathes, the 

 water is received by the gullet, and passes into the 

 gill-cells, and out again by the gill -openings in the 

 sides. This mode of breathing is incompatible with 

 adhering to substances by the mouth as a sucker ; 

 and the upper lip only has the sucking form and 

 character, so that the fish is inaccurately named the 

 ' lesser river lamprey." Its tail is lancet-shaped, by 

 :he dorsal and anal fins meeting in a point without 

 any caudal. Its general habits, mode of feeding, and 

 time of breeding arc but little known, and it has not 

 been ascertained to migrate. The probability is that 

 it follows the general law of the mud fishes, and 

 breeds in the very hottest season. Its size and ge- 

 neral appearance have caused it to be sometimes 

 confounded with the small lamprey (Pctromyzon 

 plunare). 



AMMODYTES, the launce, or "sand eel," a ge- 

 nus of soft-finned bony fishes without ventral fins, and 

 belonging to the eel-shaped family, but not partaking 

 much of that shape or of the general characters of 

 the eels. There are two species: the common launce 

 (A. tobianus), which is seldom found more than five 

 inches in length. It is a beautiful little fish, of a 

 bluish green on the upper part, with a straight line 

 of darker on each side. The under part, the head 

 and the irides are. silvery, and there are silvery re- 

 flections on the darker parts. The dorsal, anal, and 

 caudal fins are all separate from each other ; the 

 dorsal begins behind the pectorals ; and the caudal 

 is forked. The head is very slender, the upper jaw- 

 in ordinary states is the shorter, but it can be pro- 

 truded. The other species (A. lanceolntus) grows to 

 a larger size, is more slender in proportion to its 

 length, has the dorsal fin commencing as far forward 

 as the pectorals, and the upper part more inclining to 

 silver grey. They have no air bag, or coeca to their 

 intestines. They feed upon worms and the smaller 

 naked mollusca, boring in the sand with great ra- 

 pidity. 



Though but of small size, they are very interesting 

 fishes. They are caught in great numbers, are ex- 

 cellent eating, and much valued by the fishermen as 

 bait. They are understood to form the principal food 

 of some of the more valuable fishes, especially of the 

 salmon when these are in the estuaries of the rivers, 

 and in highest condition. The small sandy bays, at 

 the confluence of the lesser streams with the sea, es- 

 pecially where those streams flow through fertile dis- 

 tricts, arc their favourite haunts ; and the catching of 

 them is often a work of much bustle and amusement. 

 The favourable time for them is the spring tide ebb, 

 and the further that the tide ebbs back the better. It 

 is better also in the morning or evening, than in the 

 heat of the day ; and best of all, on those dark and 

 still evenings when evaporation is nearly suspended, 

 and the sands continue wet, and reflect the forms of 

 the people ; that state of the weather increases sound 

 as well as sight, and it enables the sand worms to re- 

 main near the surface, over a large portion of the 

 beach ; the consequence is that the launces are all 

 on the qui vive, driving through the sand in all direc- 

 tions, occasionally jerking into the air, but instantly 

 hiding themselves in the sand. 



