PAR 



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P A It 



whose opposite sides are parallel 

 and equal. 



PARALLEL'OPIPED. (parallelipipede, Fr. 

 terme de giombtrie. Corps solide 

 termini par six parallelogrammes 

 dont les opposes sont paralleles entre 

 eux.j A solid figure contained under 

 six parallelograms, the opposites of 

 which are parallel and equal ; or it 

 is a prism whose base is a parallelo- 

 gram; it is always triple to a 

 pyramid of the same base and height. 

 The term parallelepiped includes, in 

 mineralogy, all those solids whose 

 bounding planes are parallel two 

 and two; as for instance, all the 

 varieties of the rhomboid ; and all 

 the prisms of which the terminal 

 planes are rhombic; and all the 

 square and rectangular prisms which 

 do not possess the precise proportions 

 of the cube. 

 PABALLELO'PIPEDAL. Having the figure 



of a parallelepiped. 

 PARALLELISM. Nothing is more re- 

 markable in volcanic dikes than the 

 parallelism of the opposite sides, 

 which usually correspond with as 

 much regularity as the two opposite 

 faces of a wall of masonry. 

 PABAMO'UDEA. (The derivation of this 

 word, says Buckland, I could trace 

 to no authentic source, but shall 

 adopt because I find it thus appro- 

 priated.) A singular fossil body, 

 found in the chalk of the North of 

 Ireland. Among the organic 

 remains of the chalk in the north 

 of Ireland, are large silicious bodies 

 of a very peculiar character. These 

 singular fossils are found in many 

 of the chalk pits from Moira to 

 Belfast and Larne, but are most 

 numerous at Moira. They have, 

 I believe, never yet been found in 

 the chalk of England, except at 

 Whitlingham, near to Norwich, 

 and at some other places in the 

 same neighbourhood, whence there 

 is a good specimen in the collection 

 of the Geological Society, about 

 two feet long and one foot in 



diameter. The length of these 

 bodies varies from one to two feet, 

 their thickness from six to twelve 

 inches. Their substance in all 

 cases is flint. The termination of 

 of these silicious bodies is distinct, 

 and the separation of the flint from 

 its matrix f chalk always clear and 

 decided. Their outer covering has 

 the appearance of a thin epidermis, 

 smooth externally, and whiter than 

 the mass of flint enclosed, which is 

 usually of a dark grey colour. 



In all cases these bodies seem to 

 have had a central aperture passing 

 into and generally through their 

 long diameter. The breadth of 

 this aperture varies in different 

 specimens. 



PAKAMO'BPHISH. The name given to 

 a particular kind of pseudo-mor- 

 phism. 



PABA'NTHINE. A rare mineral, thus 

 named by Haiiy, more commonly 

 known as Scapolite. 

 PABASI'TA. fparasita, Lat. irapaffno?, 

 Gr.) In Cuvier's arrangement, the 

 third order of Insecta; they have 

 six legs and are apterous. The Rev. 

 Mr. Kirby observes, "the order of 

 parasites, consisting of the most 

 unclean and disgusting animals of 

 the whole class, infest man, 

 beast and bird, no less than four 

 species being attached to man, 

 may be divided into two sections, 

 namely, those that live by suction, 

 and those that masticate their food. 

 To the first of these belong the 

 human and the dog-louse, and to 

 the other the various lice that 

 inhabit the birds, of which almost 

 every species has a peculiar one." 

 PAEASI'TIC } 1. In botany, applied 

 PABASI'TICAL. j to plants which fix 

 their roots into other plants, and 

 from them, instead of from the 

 earth, derive their nourishment: 

 the mistletoe is a familiar example. 

 2. In zoology, a name given to 

 certain insects which live upon the 

 animals they infest. 



