PUD 



elves for a moment in the air, and of 

 making great leaps. There are several 

 species found in Poland, Kussia,anu Sibe- 

 ria, and also in America, and the Indian 

 Archipelago. 



PTBROPH'ORCS. A sub-genus of flssi- 

 pennate tineac, having wings with fringed 

 edges like feathers. The caterpillars have 

 sixteen feet, live on leaves, but construct 

 no tube. Name from xn-v, a wing, and 

 {*, to bear. 



PTEROP'OPA. Pteropods. A class of 

 molluscs which swim in the ocean, but 

 being deprived of feet, can neither fix 

 themselves to other bodies, nor crawl. 

 The organs of locomotion consist of fins, 

 placed like wings on the two sides of the 

 mouth: whence the name, from TT^OV, 

 a wing, and jrouy, a foot. Four genera 

 only are known, and these abound in the 

 colder regions of the ocean. 



PTER'OPUS. A sub- genus of the bat 

 tribe, found in the East Indies. It is the 

 largest bat known, and the flesh is eaten. 

 Name from jrrtjov, and KM;, a foot. 



PTOLEMA'IC. In astronomy, the Ptole- 

 maic system was that maintained by 

 Ptolemy, who supposed the earth to be 

 fixed in the centre of the universe, and 

 that the sun and stars revolved round it. 

 This theory was received for ages, but 

 was finally superseded by the Copernican 

 system. 



PTOLEMA'ITES. A sect of ancient here- 

 tics among the Gnostics. 



PCBES'CEXCE, Lat. pubescentia, from 

 pubes. In botany, this term comprehends 

 all the various downy, woolly, or hairy 

 clothing of plants, which Linne reckoned 

 the seventh of their fulcra or appendages. 



PCB'LICAN, Lat. publicanus, from pub- 

 licus. Amongst the Romans, publicans 

 were farmers of the taxes and public re- 

 venues, and the inferior officers of this 

 class were deemed oppressive. 



PU'CERON. The name of a small insect, 

 frequently found on the young branches 

 of trees and plants, often in such clusters 

 as nearly to cover them. The name is 

 French, from puce, a flea ; but the insect 

 has no resemblance to the flea, and so far 

 from hopping, it rarely walks See APHIS. 



PUCK. In medifnval mythology, a. domes- 

 tic fairy, famous for nocturnal exploits. 



PVD'DING. In nautical language, a thick 

 wreath or circle of cordage, tapering from 

 the middle towards the ends, and fastened 

 about the mast below the trusses, to pre- 

 vent the yards from falling down, should 

 the ropes sustaining them be shot away. 



PCD'DINGSTONE. A conglomerate, com- 

 posed of rounded stones imbedded in a 

 paste. The fragments composing breccia 

 me angular. 



PCD DLE (for engineering purposes). A 

 uX^Ktuie of good tempered clay and sand, 



9 PUL 



reduced to a semi-fluid state, and ren- 

 dered impervious to water by manual 

 labour. 



PUER'PERAL, Lat. puerperalis, relating 

 to child-bearing. 



PL-FF'BALL. In botany, see LYCOPERDON. 



PCF'FIN. A bird. 1. The Alca arctica, 

 I, in., is the most common species. It is 

 about the size of a pigeon, sometimes 

 breeds on the English coast, and is very 

 common on those of France during the 

 winter. See FRATERCULA. 2. The Pro- 

 cellaria puffinus, Gmelin, about the size of 

 a crow, and very common in almost every 



sea. 3. The Procellaria anglonisis, 



Temminck, about the sizeof a woodcock. 

 It breeds in immense numbers on the 

 northern coast of Scotland. 



PUP'GING. A coarse kind of mortar, 

 laid on the boards between joists. 



PU'GIL, Lat. pugillus, dim. of ptignus, 

 the fist. The eighth part of a handful. 



PDG-PILING. The same as Dovetail 

 Piling. 



PUISNE JUDGES, Fr. younger. The 

 judges and barons of the King's Bench, 

 Common Pleas, and Exchequer, are so 

 named, excepting the chief judges and 

 baron. 



PC'LEX. The Flea. A genus of apte- 

 rous insects, of the order (rather com- 

 posing the order) Suctoria, Cuv. There 

 are many species peculiar to quadrupeds 

 and birds. They also attack the human, 

 subject, but are not natural to man. 



PUL'LEY. In mechanics, one of the sim- 

 ple machines or mechanical powers. The 

 term is stricfJy applicable to the small 

 wheel turning on a pin in a block, with a 

 furrow or groove, in which runs the rope 

 that turns it. The word is now, however, 

 used in the general sense of tackle, to de- 

 note all parts cf the machine for raising 

 weight, of which the pulley forms a 

 part. The first tut is an example of the 



o 



single pulley, the second of a sysu-oi of 



pulleys. 



