526 



Erearfurp of Natural 



diterranean. They are distinguished by 

 having the elytra soldered together ; the 

 wings rudimental or obsolete ; the palpi fili- 

 form ; the mandibles bifid at the tips ; and 

 the maxillas concealed by the mentum, which 

 is very large, and not narrowed at the base. 

 Their colours are black or obscure ; they are 

 exceedingly sluggish, and on being alarmed 

 they emit a disagreeably fetid fluid. 



PIMELODUS. A genus of malacoptery- 

 gious abdominal fishes, separated by La- 

 cepede from the genus Silurtis of Linnaeus : 

 by modern Ichthyologists again this genus is 

 subdivided. The head 

 is depressed ; there are 

 two dorsal fins, the se- 

 cond adipose. There are 

 very many species of this 

 group, found chiefly in 

 South America, the Nile, 

 and some of the Eastern 

 rivers. We figure a small 

 species discovered by M. 

 Humboldt in the king- 

 dom of Quito, where it 

 lives in streams, and is 

 only occasionally eaten 

 by the very poorest of the 

 Indians. This species 

 has two cirri on the head; 

 it is of an olive colour, 

 sprinkled with small 

 black spots, and is about 

 four inches long ; but the 

 striking fact whence it 

 derives its specific name, 

 (P. Cydopum)i$ its being 

 found sometimes in thou- 

 sands, ejected from the 

 crater or the apertures 

 on the sides of volcanoes. The inhabit- 

 i ants know them well, and call them pre- 

 ', tuulilhts. They are believed to abound in 

 ! subterraneous lakes, and only to be found 

 1 by accident in the streams. On emerging 

 : from the crater they are found so little 

 ; changed, that they can always be recognized: 

 ; a proof that the heat of the water thrown up 

 : from the volcano can have little effect on 

 j them : this may in part be owing to the 

 mucilage with which they are covered. 

 PINE MARTEN. [See MAKTEN.] 

 PINION [MOTHS]. A name applied by 

 collectors to different species of Moths, of 

 the genus Cosmia. 



PINNA. A genus of Mollusca, called also 

 the Wing-shell, which in many respects ap- 

 I proaches the Mussels. It has two equal 

 wedge-shaped valves, united by a ligament 

 along one of their sides ; and attains a very 

 considerable size, sometimes being nearly 

 three feet long. The animal fixes itself, by 

 its byssus, which is remarkably long and 

 silky, to submarine rocks and other bodies ; 

 where it lives in a vertical position, the point 

 of the shell being undermost, and the base 

 or edge above. Sometimes large quantities 

 of them are even found attached to a sandy 

 bottom at the depth of a few fathoms. They 

 are common in some parts of the Mediter- 

 and are not merely sought as food 



by the inhabitants on the coasts, but they 

 gather the byssus, of which a stiift' may be 

 formed that is remarkable for its warmth and 

 suppleness. The filaments are extremely 



fine and strong, and the colour, which is a 

 reddish-brown, never fades. The finest bys- 

 sus of the ancients was fabricated from these 

 filaments ; and in Sicily they are still some- 

 times manufactured into gloves and other 

 articles of dress, though, it must be confessed, 

 more as an object of curiosity than for use. 



PINNIPEDES. A group of Decapodous 

 Crustacea, met with at a distance from the 

 coasts. They are characterized by having 

 the hind pair of legs terminated by a flat- 

 tened plate for swimming. The most notice- 

 able of these swimming or shuttle-crabs, as 

 they are termed, are the exotic species com- 

 posing the genus Ufatuta, which have the 

 carapax nearly circular, and armed on each 

 side with a strong spine, and with the four 

 posterior pairs of legs terminated by a di- 

 lated plate for swimming. Some of the 

 smaller species, found on our own coasts, 

 are exceedingly abundant, and furnish the 

 lower orders in London and elsewhere with 

 an article of food. 



PINNOTHERES, or OYSTER CRAB. 

 A genus of Decapod Crustaceans, of very 

 small size (some of them called Pea-crabs), 

 which reside, during a portion of the year at 

 least, inside various bivalve shells, such as 



mussels, &c. The carapace of the females | 

 is suborbicular, very thin and soft ; whilst I 

 that of the males is firmer and nearly glo- 

 bular, and rather pointed in front ; the legs j 

 are of moderate length, and the claws of the j 

 ordinary form ; the tail of the female is very 

 ample, and covers the whole of the under 

 side of the body. The ancients believed that 

 the Pea-crab lived upon the best terms with 

 the inhabitant of the shell in which it was 

 found ; and that they not only warned them 

 of danger, but went abroad to cater for them. 



PINTAIL DUCK. (Dafila acuta.) This 

 is an elegantly formed, long-bodied Duck, 

 the neck longer and more slender than most 

 others. It is a shy and cautious bird, feeding 

 in the mud flats and shallow freshwater 

 marshes, but rarely resides on the sea coast. 



