}90pttlar 2B(rtfmiarg at 



feature. 



35 



long ; tlie body is of a reddish colour ; and 

 on being touched, exudes a quantity of yel- 

 low fluid. The animal bores for itself a 

 passage through the sand, and secures the 

 sides of the passage from falling in by apply- 

 ing to them a glutinous cement, which unites 

 the particles of sand into a kind of wall or 

 coating. This covering does not adhere to 

 the body, but forms a detached tube, within 

 which the animal moves with perfect free- 

 dom, and which it leaves behind it as it 

 progressively advances ; so that the passage 

 is kept pervious throughout its whole length, 

 by means of the lining, which may not in- 

 aptly be compared to the brickwork of the 

 shaft of a mine or tunnel. 



ARENICOLI. The name given to a 

 section of beetles which live in dung, and 

 form deep burrows in the earth. The elytra 

 entirely cover the abdomen ; the mandibles 

 are horny, exposed, and curved ; the terminal 

 lobe of the maxillae is generally straight ; 

 and the antennae are ten or eleven-jointed. 

 They fly about in the twilight after sunset, 

 and counterfeit death when alarmed. 



ARGALI. A species of wild Sheep, found 

 on the mountains of Siberia and Kamts- 

 chatka. It so closely resembles the MOUFFLON 

 [which see] as to be regarded by many natu- 

 ralists as the same species. 



ARGENTINE. (Argentina sphyrcena.) 

 A genus of Malacopterygious fishes belong- 

 ing to the Salmonidce ; the mouth of which 

 is small and toothless ; the tongue is fur- 

 nished with strong hooked teeth ; and the 

 digestive organs resemble those of the Trout. 

 The well-known species Argentina sphyrcena 

 is caught in the Mediterranean, and is com- 

 mon in the markets of Rome : it has also, 

 though very rarely, been caught on the 

 British coast. It is about two inches and a 

 half in length ; the eyes are large, and the 

 irides silvery ; the lower jaw much sloped ; 

 the teeth small ; the body compressed, and 

 of an equal depth almost to the anal fin ; 

 and the tail forked. The back is of a dusky 

 green ; the sides and covers of the gills ap- 

 pear as if overlaid with silver : on each side 

 of the belly is a row of circular punctures, 

 and above them another which terminates 

 near the vent. The air-bladder is thick, and 

 loaded with nacre, the substance used in 

 making artificial pearls. 



ARGONAUT, or PAPER-NAUTILUS. 

 A curious molluscous animal, the shell of 

 which is peculiarly white and delicate ; not 

 chambered, as in the true Nautilus, but pos- 

 sessing one spiral cavity, into which the 

 animal can withdraw itself entirely. It has 

 eight arms, two of which expand into wide 

 membranous flaps ; and as the animal floats 

 on the surface of the sea, the expanded 

 membranes are spread over the sides of the 

 shell, where, meeting along its keel or edge, 

 they are said to be held in close contact by a 

 double row of suckers, and thus completely 

 inclose it. Such being the structure and 

 action of the Argonauta, it is not surprising 

 that it has had the reputation, from very 

 early times, of using its arms as oars, and 

 spreading these expanded membranes as 



sails, so as to be wafted along by the wind. 

 [See NAUTILUS.] 



The nature and habits of the Argonauta 

 having long been a subject of much contro- 



versy, a lady (Madame Jeannette Power) 

 made a series of interesting experiments, in 

 18S, the result of which she laid before the 



Academy at Catania. In order to arrive at 

 her conclusions, she had cages constructed, 

 and placed in a shallow part of the sea, near 

 the citadel of Messina, and in these cages she 

 inclosed several of the living animals, wliich 

 she kept supplied with small molluscs, their 

 natural food. The result of her observations 

 went to prove that the animal is in the ha- 

 bit of sailing on the water, using its dilated 

 tentacula as sails, the remainder as oars, 

 and aiding its movements by means of a 

 kind of proboscis which it employs as a helm. 

 The sail, when spread out, presents a silvery 

 surface, speckled with concentric circles of 

 spots, with a black spot in the middle, sur- 

 rounded with a beautiful gold colour. The 

 animal is not attached to the shell, but, when 

 under water, it adheres firmly to it by its 

 sail-arms. The shell, which is remarkably 

 brittle when exposed to the air, is quite pli- 

 able in water, and thus escapes the destruc- 

 tion to which so thin and tender a fabric 

 would otherwise be liable. The animal at 

 the approach of any object takes in its tenta- 

 cula, wraps its gaili over the shell, and de- 

 scends, blackening the water at the same 

 time, if hard pressed, by a discharge of inky 

 fluid, to cover its escape. 



ARGULUS. A genus of Crustaceous ani- 

 mals, belonging to the P.SCILOPODA. The best 

 known species, Arfftilusfoliacevs, is found in 

 this country. This aquatic parasite attaches 

 itself to the young of Frogs, Sticklebacks, &c., 

 and sucks their blood : it is also found upon 

 the Perch, Pike, Carp, and Trout. The 

 body is flattened ; of a greenish-yellow 

 colour ; less than a quarter of an inch long ; 

 and is divided into five somewhat indistinct 

 segments along the back. The animal turns 

 itself about in the water in a similar manner 

 to the Gyrini. The eggs are oval, of a milky 

 white colour, and are attached by gluten to 

 stones or other hard substances ; and before 

 the Argulus arrives at the adult state it 

 undergoes several transformations. 



ARGUS-PHEASANT. (Argus gigantetts.) 

 This beautiful but rare bird is a native of 



