USED IN NATURAL HISTORY. 



when it opens to the left, sinis- 

 tral. 



DEXTRAR'SUM. Twining from left 

 to right. 



DIA. Gr. Through: a prefix which 

 denotes extension, perversion, tran- 

 sition. 



DIADE'LPHIA. fr. gr. dis, two; del- 

 phos, brotherhood. Name of a 

 Linnaean class of plants. 



DIADE'MA. Lat. A diadem, acrown. 

 A germs of echini'dese. (p. 54, 

 Book viii). 



DI'AGRAM. fr. gr. dia, through ; gra- 

 plio, I write. A figure drawn for 

 illustration. 



DIA'LLAOE. fr. gr. diallage, differ- 

 ence. A mineral of foliated struc- 

 ture easily divisible in one direc- 

 tion, its natural joints and frac- 

 tures exhibiting a very different 

 lustre and appearance. 



DIAMARNETIC. If a bar of iron be 

 suspended between the poles of 

 an electro-magnet, it will be at- 

 tracted by both poles on the line 

 of force. But if a bar of bismuth 

 be suspended in the same man- 

 ner, it will be repelled by both 

 poles, and rest at right angles to 

 the line of force. Substances 

 which are attracted by both poles 

 of an electro-magnet are said to 

 be magnetic, and those which are 

 repelled by both poles are termed 

 diamagnetic. 



DIA'NDRIA. fr. gr. dis, two; aner, 

 stamen. Name of a class of 

 plants. 



DIA'JTDROUS. Having two stamens. 



DIA'PUAXOUS. fr. gr. dia, through ; 

 phainein, to shine. Permitting the 

 passage of light. 



DI'APHRAGM. fr. gr. diaphragma, a 

 partition. The fleshy or muscu- 

 lar partition between the cavity 

 of the chest and cavity of the ab- 

 domen. The midriff. 

 L i A'STOLE. fr. gr. diastello, I open, 

 dilate. The dilatation of the 

 heart and arteries when the blood 

 enters their cavities. 



DIBRA'X CHIAL. Having double gills 



or branchiae. 



DI'BRANCHIA'TA. fr. gr. dis, two; 

 bragchos, gills : two-gilled. Name 

 of a division of cephalopods. 

 DICE'RAS. fr. gr. dis, two; keras, 

 horn. Generic name of a fossil 

 bivalve, (p. 64, fig. 106, Book 

 viii). 



DICHO'TOMA. } fr.gr. dicha, divided; 



DICHO'TOMUM. > tomos, section. Di- 



DICHO'TOMUS. j cho'tomous. In zoo- 

 logy this term is applied to a spe- 

 cies of the genus Iris, the body 

 of which is bifurcate. In botany 

 it is applied to the stem, branches, 

 peduncles, leaves, hairs, styles, 

 &c., when they are bifurcated in 

 form. 



JB. fr. gr. dis, two; klinos, 

 bed. Name of a division of 

 plants. 



us. fr. gr. dis, two ; kline, 

 bed. Having the stamens in one 

 flower and the pistils in another. 



Dicoc'cous. Having two cocci; 

 containing two grains of seed. 



DICOTY'LEDOX. fr. gr. dis, two ; ko- 

 tulcdon, seed-lobe. A double seed- 

 lobe. 



DICOTY'LEDONS. fr. gr. dis, two; 

 kotuledon, seed-lobe. A division 

 of plants, according to the Natu- 

 ral Order. 



DICOTYLE'DOSTOCS. Relating to di- 

 cotyledons. 



DfuA'cxYLE. fr. gr. dis, twice ; dak- 

 tulon, a finger or toe. Two-fin- 

 gered. Applied to various ani- 

 mals which have two digits on 

 their extremities. 



DIDEL'PHIDJE. A tribe of marsupial 

 mammals. 



Di DEI/PHIS. fr. gr. dis, twice or 

 double; delphus, a wornb. The 

 name of a genus of the order of 

 marsupialia. 



DIDEL'PHOUS. fr. gr. dis, double; 

 delphus, womb. Applied to opos- 

 sums and other marsupial mam- 

 mals. 



DI'DYMOUS. Two united 



3 A2 



