PLE 



PLE 



share of business. Their habits bring 

 them closely connected with uttoniies. 



PLEASURE and Pain, says Mr Locke, 

 are simple ideas, whicn we receive both 

 from sensation and reflection ; there be- 

 ing thoughts of the mind, as well as sen- 

 sations, accompanied with pleasure or 

 pain. 



PLECTRANTHUS, in botany, a genus 

 of the Didynamia Gymnospermia class and 

 order. Natural order of Verticilluta:. La- 

 biatse, Jussieu. Essential character : ca- 

 lyx upper segment larger ; corolla resu- 

 pine, gibbous or spurred at the base ; fila- 

 m'ents simple. There are five species, 

 natives of Africa and Arabia Felix. 



PLECTRONIA, in botany, a genus of 

 the Pentandria Monogynki class and or- 

 der. Natural order of Contorts. Rham- 

 ni, Jussieu. Essential character : petals 

 five, inserted Jnto the throat of the calyx; 

 berry two-seeded, inferior. There is but 

 one species, viz. P. ventosa, a native of the 

 Cape of Good Hope. 



PLEIADES, in astronomy, an assem- 

 blage of seven stars in the neck of the 

 constellation Taurus, the bull ; although 

 there are now only six of them visible to 

 ihe naked eye. The largest is of the 

 third magnitude, called " lucido pieia- 

 dum." 



PLENUM, in physics, denotes, accord- 

 ing to the Cartesians, that state of things 

 wherein every part of space is supposed 

 to be full of matter; in opposition to a 

 vacuum. 



PLENUS/05, in botany, a full fower ; 

 a term expressive of the highest degree 

 of luxuriance in flowers. The petals in 

 full flowers are so multiplied as to ex- 

 clude all the stamina, and frequently to 

 choak up the female organ, so that such 

 flowers, though delightful to the eye, are 

 vegetable monsters. Flowers with more 

 than one petal, are most liable to this ; 

 such are the ranunculus, anernony, pop- 

 py, myrtle, &c. &.c. Flowers with one 

 petal only are but seldom subject to this 

 fulness ; these, however, are not totally 

 exempt, as may be seen in the double po- 

 lyanthus, hyacinth, crocus, &c. In flow- 

 ers with oae petal, the mode of luxuri- 

 ance, or impletion, is by a multiplication 

 of the divisions of the limb, or upper part. 

 In flowers with more than one petal, by 

 a multiplication of the petals of necta- 

 rium. 



PLEURISY, in medicine, a violent pain 

 in the side, attended with an acute fever, 

 a cough, and a difficulty of breathing. 



PLEURONECTES, the/<mwrf-, in na- 

 tural history, a genus of fishes of the OF. 



VOL. v, 



der Thoracici. Generic character: the 

 eyes spherical, and both on the same side 

 of the head; mouth arched; body com- 

 pressed, one side representing the back, 

 ami the other the abdomen. In this ge- 

 nus are Comprehended all that are com- 

 monly denominated flat fish. They swim 

 obliquely, and are observed generally at 

 the bottom of the water, being destitute 

 of the air bladder. They often ingulph 

 themselves in sands as far as the head., 

 and thus elude the attacks of many ene- 

 mies. The eyes of some of this genus are 

 towards the right when the fish' presents 

 its abdomen to the spectator, and those 

 of others towards the left. This differ- 

 ence constitutes the principal division oT 

 this genus. 



P. nippogtossus, or the holibiit, is one 

 of the largest of fishes, being sometimes 

 found of four hundred pounds weight. 

 It subsists on smaller fishes, and on vari- 

 ous kinds of crabs and shell fish It i3 

 considered as rather coarse for the table, 

 when particularly large, and the part 

 nearest the fins is thought by far prefer- 

 able to any other. It is found in the Eu- 

 ropean and North American .seas. 



The P. platessa, or plaise, is distinguish- 

 able from the other species, by being 

 marked on the body and fins by numerous 

 orange coloured spots. This fish inhabits 

 the same seas as the former, and is some- 

 times taken of the weight of fifteen pounds, 

 though one of eight is considered in Eng- 

 land as very large. They are in consi- 

 derable estimation, and are thought pre- 

 ferable when of a moderate size. They 

 subsist on the same food as the former. 



The P. limanda, or dab, inhabits the 

 same seas, but is far less common. It is 

 much smaller than the last, but thought 

 far more delicate for the table. It is in 

 the greatest perfection in the spring 

 months. 



P. flesus, or the flounder, is formed 

 much like the plaise, but is smaller, and. 

 destitute of the orange spots; it inhabits 

 the same seas, and abounds on the British 

 coasts, and frequently ascends the rivers 

 to a considerable height. 



P. solea, or the sole, is found in the Eu- 

 ropean and American seas, and is some- 

 times two feet long, and eight pounds in 

 weight ; but, in general, very considerably 

 smaller. Its scales may be distinguished 

 by the microscope for their peculiar ele- 

 gance of structure. Soles are fond of ly- 

 ing at the bottom of the waters which 

 they frequent, and are caught by trawl 

 nets. Their flesh is extremely firm and 

 rich, and is preferred to that of any othe? 



3 F 



