CHY 



and of which, as well as of the Indian 

 churn, an accurate description is given 

 in the Agricultural Magazine for Octo- 

 ber, 1807, merit particular attention, for 

 their great simplicity and many good 

 qualities. 



CHYLE. See CHYME, ASSIMILATION, 

 &c. 



CHYME, in animal economy : in the 

 process of digestiou, the food is subject- 

 ed to a temperature usually above 90 of 

 Fahrenheit ; it is mixed with the gastric 

 juice, a liquor secreted by the glands of 

 the stomach, and is made to undergo a 

 moderate and alternate pressure, by the 

 contraction of the stomach itself. It is 

 thus converted into a soft uniform mass 

 of a greyish colour, in which the prev ious 

 texture or nature of the aliment can be 

 no longer distinguished. 



The chyme, as this pulpy mass into 

 which the food in the stomach is resolv- 

 ed is termed, passes by the pylorus into 

 the intestinal canal, where it is nuxed 

 with the pancreatic juice and the bile, 

 and is still exposed to the same tempera- 

 ture and alternating pressure. The thin- 

 ner parts oi it are absorbed by the slen- 

 der tubes termed the lacteals. The li- 

 quor thus absorbed is of a white colour : 

 it passes througn the glands of the me- 

 sentery, and is at length conveyed by the 

 thoracic duet into the blood. This part 

 of the process is termed chylification, 

 and the white liquor thus formed, chyle. 

 It is an opaque milky tiuid, mild to the 

 taste. By standing for some time, one 

 part of it coagulates; another portion is 

 coagulated by heat. 



The chyle, after mixing with the 

 lymph conveyed by the absorbent ves- 

 sels, is received into the blood which has 

 returned from the extreme vessels, and 

 before it passes to the heart. All traces 

 of it are very soon lost in the blood, as it 

 mixes perfectly with that fluid. It is 

 probable, however, tbat its nature is not 

 immediately completely altered. The 

 blood passing from the heart is convey- 

 ed to the lungs, where it circulates over 

 a very extensive surface presented to 

 the atmospheric air, with the interven- 

 tion of a very thin membrane, whicli 

 does not prevent the,r mutual action. 

 During this circulation, the blood loses a 

 considerable quantity of carbon, part of 

 which, it is probable, is derived from the 

 : mperfectly assimilated chyle, as this, 

 originating in part from vegetable mat- 

 ter, must contain carbon in larger pro- 

 portion than even the blood itself. See 

 ASSIMILATION, 



CIC 



CICADA, in natural history, a genus of 

 insects of the order Hemiptera. Generic 

 character : snout inflected ; antennae seta- 

 ceous; the four wings membranaceous 

 and deflected ; legs in most of the spe- 

 cies formed for leaping. These insects 

 live on various plants ; the larva is apte- 

 rous ; the pupa furnished with the mere 

 rudiments of wings; both of them six 

 footed and active, the male of the per- 

 fect insect chirps like the cricket. There 

 are some hundred species noticed and 

 described by different authors, and enu- 

 merated with their characters by Gmelin. 

 There are three divisions. A." antennae 

 subulate, inserted in the front. B. legs not 

 formed for leaping. C. antennae filiform, 

 inserted under the eyes ; this class is sub- 

 divided into, 1. a. lip abbreviated, trun- 

 cate, emarginate ; and, 2. b. lip rounded, 

 setaceous at the tip. The most common 

 of the European species, is C flebeia, 

 which has been long confounded with 

 the grasshopper. It is a native of the 

 warmer parts of Europe, appearing in 

 the hotter months, and continuing its 

 chirping during the greater part of the 

 day, generally sitting among the leaves 

 of trees. The insects proceed from 

 eggs deposited by the parent in and 

 about the roots of trees, near the ground. 

 They hatch into larva, in which state they 

 continue nearly two years,cast their skins, 

 and produce the complete insect. The 

 male cicada alone makes the chirping, the 

 female being entirely mute ; the noise of 

 the former proceeds from a pair of con- 

 cave membranes, seated on each side the 

 first joint of the abdomen : the large con- 

 cavities of the abdomen, immediately 

 under the two broad lam ell x- in the male 

 insect, are also faced by a tlun, pellucid, 

 irridescent membrane, serving to increase 

 and to reverberate the sound, and a strong 

 muscular apparatus is exerted, for *he 

 purpose of moving the necessary ovgns. 

 Among 1 the smaller European species is 

 C. spumaria, or j.uckow-sp-t cicada s so 

 named from the circumstance of its 

 larva being found constantly enveloped 

 in a mass of vvj^te froth, adhering to the 

 leaves and .it rvn of vegex.tuies. This 

 frotb, which is popularly known by the 

 name of cuckow-spittle, is found in the 

 summer, and is the production of the in- 

 cluded larva, which, from the time of its 

 hatching ri-nm the egg deposited by the 

 pur cut insect, continues, at intervals, to 

 SUCK the juices of the stem on which it 

 rt>'des, and to discharge them from the 

 vent in the form of very minute bubbles ; 

 and by Continuing the operation, com- 



