GYP 



GYR 



which they were rendered motionless, 

 and to all appearance dead, by it. It ap- 

 pears that the electrical fisn has no teeih, 

 and the most minute examination of the 

 fishes contained in their stomachs could 

 discover no marks of laceration, even in 

 the slightest degree. Gymnotes of three 

 feet in length are incapable of swallowing 

 any fish larger than three inches and a 

 half. It appears that the strength of their 

 peculiar talent is in proportion to their 

 magnitude, and it is stated that there are 

 some in Surinam river, whose length is 

 twenty feet, and whose shock is followed 

 by immediate death to any human being, 

 who is so unfortunate as to be exposed lo 

 it. It is observed, that even after the 

 , electrical fish is dead, it retains, for a 

 considerable time, more or less of this 

 singular property. It is a fish greatly and 

 justly dreaded by the inhabitants of those 

 countries, the rivers of which it fre- 

 quents; it is, however, notwithstanding 

 this circumstance, used by them for food, 

 and even by some considered as a capital 

 delicacy. For a representation of the 

 gymnotus electricus, see Pisces, Plate 

 IV. fig. 5. 



GYNANDRIA, in botany, the name of 

 the twentieth class in the Linnaean sys- 

 tem. It consists of plants with hermaphro- 

 dite flowers, in which the stamina are 

 placed upon the style, or upon a pillar- 

 shaped receptacle resembling a style, 

 which rises in the middle of the flower, 

 and bears both the stamina and pointal. 

 There are seven orders in this class, each 

 of which is founded on the number of the 

 stamina in the plants which compose it. 

 See BOTANY. 



GYNOPOGON, in botany, a genus of 

 the Pentandria Monogynia class and or- 

 der. Natural order of Apocineae, Jus- 

 sieu. Essential character : calyx half five- 

 cleft, inferior, permanent; corolla five- 

 parted, tube ventricose below the tip, 

 throat contracted ; stigma globular, two- 

 lobed ; berry pedicelled, sub-globular; 

 seed cartilaginous, sub-bilocular. There 

 are three species, natives of the islands 

 in the South Seas. 



GYPSIES. There are several statutes 

 against them, by which they are treated 

 as rogues and vagabonds. 



GYPSOPIIILA, in botany, a genus of 

 the Decnndria Digynia class and order. 

 Natural order of Caryophyllei. Essential 

 character : calyx one-leafed, bell-shaped, 

 angular; petals five, ovate, sessile ; cap- 

 sule globular, one-celled. There are 

 twelve species. 



GYPSUM, a substance well known to 

 the ancients, and one that is very abun- 



dant in nature, and is now denominated, 

 according to the new chemical arrange- 

 ment, the sulphate of lime. It forms im- 

 mense strata, composing entire moun- 

 tains ; it is found in almost every soil, ei- 

 ther in greater or less quantities ; it is 

 contained in the waters of the ocean, and 

 in almost all river and spring water. la 

 these its presence is the cause of the 

 quality termed hardness, which may be 

 known by the water being incapable of 

 forming 1 a solution of soap, the sulphuric 

 acid seizing on the alkali of the soap, and 

 the oil forming a compound with the 

 lime. Sulphate of lime is insipid, white, 

 and soft to the touch. Water will not 

 hold a 500th part of it in solution. Ex- 

 posed to heat it appears to effervesce, 

 which phenomenon is caused by the ex- 

 pulsion of water. It becomes opaque, 

 and falls into powder. This powder, 

 when its water has been driven off by the 

 application of a red heat, absorbs water 

 rapidly, so that if it be formed into a paste 

 with water, it dries in a few minutes. In 

 this state it is called plaster of Paris, and 

 is employed for forming casts, and for a 

 variety of purposes in the art of statu- 

 ary. 



GYRINUS, in natural history, water- 

 flea, a genus of insects of the order Cole- 

 optera. Antennae cylindrical ; jaws horny, 

 one-toothed, sharp-pointed; eyes four, 

 two above and two beneath ; thorax and 

 shells margined, the latter shorter than 

 the body; legs formed for swimming. 

 The insects of this genus are to be found 

 on the surface of waters, on which they 

 run, and describe circles with a great 

 degree of swiftness; when attempted to 

 be taken they plunge to the bottom, 

 drawing after them a bubble very similar 

 to a globule of quicksilver. Eleven 

 species of the gyrinus have been describ- 

 ed, of which one only is found in Europe; 

 and in the United States about six addi- 

 tional ones, viz. G. natator, a small insect, 

 not more than a quarter of an inch long, 

 of a blackish colour, but with so bright a 

 surface as to shine like a mirror in the 

 sun. The larva is of a very singular as- 

 pect, having a lengthened body, furnish- 

 ed with many lateral appendages down 

 the body, exclusively of six legs. Dr. 

 Shaw says, its motions are extremely 

 agile, swimming in a kind of serpentine 

 manner, stnd preying on the smaller and 

 weaker water- insects, minute worms, &c. 

 It is a highly curious object for the micro- 

 scope. When its change arrives, it forms 

 for itself a small oval cell or case on a 

 leaf of some water plant, and after casting- 

 its skin it becomes a chrysalis. These 



