SILPHEUM SILURUS. 



687 



Fumigating-bottle . 



Day labour, men and women 



Total 

 Ground rent and interest of capital 



674 

 90 



764 



which sum being subtracted from 1563. 18. the value 

 of GOOlbs. of cocoons will leave a net profit of 799 

 livres (thirty of which equal a pound sterling). 



In India considerable quantities of silk are ob- 

 tained from the cocoons of several large species of 

 moths belonging to the genus Saturnia: of these the 

 most important are the Tusseh, Arrindi, Bughy, and 

 Koligurra silk-worms ; of the two former of these an 

 interesting memoir is given by Dr. Roxburgh in the 

 Liunrran Transactions, and of the last by Lieut. Col. 

 Sykes in the Transactions of the Royal Asiatic So- 

 ciety. The Tusseh worms are the caterpillars of the 

 Saturnia Papfiia, Linnaeus, and are found in such 

 abundance in the neighbourhood of Bengal as to 

 afford a constant supply of very durable coarse dark- 

 coloured silk, which is woven into a cloth much worn 

 by the Brahmins and some other sects, and which is 

 of so great durability, that after nine or ten years' 

 wear it does not show any signs of decay. The 

 Arrindi silk-worrn is the caterpillar of the Pkaltsna 

 (.'i/nlliia, Drury, and feeds on the leaves of the Palma- 

 Christi ; its cocoons are exceedingly soft and flossy, 

 so that it is impossible to reel it off, it is accordingly 

 spun like cotton, and the thread thus manufactured 

 is woven into a coarse white cloth of loose texture, 

 but of such considerable durability, that the life of a 

 single person is seldom sufficient to wear out a gar- 

 ment made of it. It is used not only for clothing, 

 but for packing fine cloths, &c. (Introd. to Ent. i., 

 p. H3G). 



SILPHEUM (Linnfcus). A genus of North Ame- 

 rican perennial herbs, belonging to Composites. They 

 are tail-growing plants, and suitable for the -interior 

 of shrubberies, and are increased bv division. 



.SILPHID/E (Leach). A family of coleopterous 

 insects belonging to the section Pcntaincm, and sub- 

 section Xccrophaga, having five distinct joints in ail 

 the tarsi, and the mandibles terminated in an entire 

 point, and not notched. The antennas often termi- 

 nated in a perfoliated mass of four or five joints ; 

 tiie maxilla? often armed with a corneous tooth ; 

 the anterior tarsi are often dilated, and the elytra are 

 in general furnished with a raised lateral margin. 

 These insects are generally of obscure colours, and 

 subsist upon carcasses, bones, and other putrefying 

 matters, they are consequently of great service in 

 removing much infectious matter, which might other- 

 wise render the atmosphere unwholesome. The 

 larva? reside in the same situations, and are furnished 

 with six legs, and two or more anal appendages. 

 The genera are Necrophorus, ^ccrodes, Oiceoptoma, 

 Si/}>/ia, Phosphuga, Agyrtes, Peltis, Spheritcs, and 

 iNccrophilus ; those printed in italics being inhabi- 

 tants of this country. The most interesting genus is 

 that which contains the sexton beetles NECROPHOKUS, 

 which see. The genus fiifpba, as now restricted, 

 Comprises those species which have the antennae 

 gradually clavate, the club being four-jointed, the 

 elytra rounded behind, and the body depressed and 

 shield-shaped. The majority of the species are black 

 or pitchy in their colours, and frequent carrion, &c.; 



but in the Silpha quadrimaculata, Linnaeus, the thorax 

 and elytra are pale, buff-coloured, with black spots ; 

 and, in accordance with its various hues.it is found in 

 trees, amongst the foliage of which it lurks about for 

 the purpose of seizing upon and devouring lepido- 

 pterous caterpillars. 



SILVER. This valuable metal occurs in many 

 parts of the globe, and in a variety of combinations. 

 Native silver has the general characters of the pure 

 metal. It is found in masses, sometimes ramifying 

 into arborescent and capillary forms. At other times 

 it is crystallised in cubes and octohedra. The richest 

 known mines are found in Peru and Mexico. Europe 

 also presents some valuable mines, but they are prin- 

 cipally confined to Saxony, Bohemia, and Norway. 

 It is true that both Cornwall and Devonshire present 

 some fine specimens, but silver can hardly be placed 

 amongst the mineralogical treasures of this country. 

 It may, however, be proper to add, that silver was 

 once found in considerable quantities in Stirlingshire, 

 but the vein has been long exhausted. 



SILURUS, or rather SILUKID/E, a family of fishes 

 which have no English name, nor is there any well- 

 authenticated account of even a single specimen 

 occurring in any part of the British islands, though 

 Sir Robert Sibbald names it in his Appendix to the 

 River Fishes of Scotland; and subsequent writers 

 upon British fish have, upon this authority, included 

 it in their lists. 



The Siluridce are soft-finned fishes with abdominal 

 fins, and in Cuvier's arrangement they follow imme- 

 diately after the pike family. They are very peculiar 

 fishes, and may be looked upon as the family in 

 which a section of the abdominal finned fishes ter- 

 minates. They are wholly fresh-water fishes, or, at 

 least, the only sea in which they have been found 

 is the Baltic, and it contains much less salt than the 

 ocean generally, and so little indeed in some places 

 as to be available for culinary purposes. Generally 

 speaking, they are of clumsy and unwieldy form and 

 size. They chiefly inhabit the mud at the bottom of 

 rivers and some lakes, but mostly the former ; and 

 their powers in swimming are sluggish, and performed 

 by the flexures of the body, in the manner of those of 

 an eel, rather than by the simple but vigorous action 

 of the caudal fin. The character of their flesh cor- 

 responds with this sluggish habit, for, though gene- 

 rally of good flavour, it is too rich for being easily 

 digested. They also accumulate a great deal of fat, 

 and the fat upon them has some slight resemblance 

 to the lard of pigs. 



There is only one species found in Europe, and 

 that chiefly in the larger rivers of the north, espe- 

 cially those which discharge their waters into the 

 Baltic. But in the rivers of the warmer climates, 

 especially in those of Africa, they are much more 

 abundant both in numbers and in species ; and they 

 were placed among the sacred fishes by the ancient 

 Egyptians. They are exceedingly voracious ; but, 

 in consequence of the inferiority of their swimming 

 powers, they are unable to capture prey by chasing 

 it, and therefore their habit is to lie in wait, and 

 seize their food by surprise. As is the case with 

 most, if not all, of the lurking fishes which wait at the 

 bottom for such prey as may swim over them, they 

 are furnished with barbules or feelers, which vary in 

 number in different members of the family, but of 

 which two in the upper jaw are generally in so far 

 supported by the maxillary bones, by means of which 



