DENDRIFORM 



97 



DERIVED 



dron, tree ; herpeton, reptile.] A reptile of 

 the lizard, kind, two species of which were 

 found in a tree in the lower Coal Measure. 



Dendriform, (den'dri-form). [Gk. dendron, 

 tree.] Tree-like. 



Dendrites, (den'drits, or den-drl'tez). [Gk. 

 dendron, tree.] Any veins of altered or 

 foreign matter, in rocks, which have a 

 "branching or tree-like appearance. 



Dendrobium. [Dendron, tree: bios, life.] 

 Orchidaceae : q.v. grow on trees. 



Dendrocoeli, (dea-dro-seli). [Gk. dendron, 

 tree; koilia, intestines.] Used by Siebold 

 for a sub-division of Turbellarii, including 

 those whose intestines are branched in a 

 tree-like manner. 



Dcndrodus, (den'dro-dus). [Gk. dendron, tree; 

 odous, tooth.] A fish, belonging to Holop- 

 tychus, known only by fossil teeth, which 

 have a branch-like tissue. 



Dendrohyrax, (deri-dro-lu'raks). [Gk. den- 

 dron, tree; Hyrax, q.v. ] An arboreal 

 species of Hyrax, q.v. 



Dendroid, (den'droid). [Gk. dendron, tree; 

 eidos, forra.]=Tree-like. 



Dcadrolagus, (den-drol'a-gus). [Gk. dendron, 

 tree; lagos, hare.] A species of kangaroo, 

 found in New Guinea, adapted to tree life. 



Dendrolitharia, (den-dro-li-tha'ri-a). [Gk. den- 

 dron, tree; lithos, stone.] De Blainville's 

 terra for coral polyps. 



Dendrophyllia, (den-dr5-fil'li-a). [Gk. den- 

 dron, tree ; phyllon, leaf.] A coral polyp 

 which buds into a tree-like form. 



Dendropupa, (den-dr5-pu'pa). [Gk. dendron, 

 tree; L. pupa, puppet. ]= Pupa vetusta : a 

 land snail, known by shells found in paleo- 

 zoic rocks. 



Deneb=a Cygni : a star in the constellation 

 Cygnus. 



Denebola=j3 Leoiiis : a star in the constel- 

 lation Leo. 



Denominator, (dc-nom'i-nil-tor). [L. deno- 

 mino, I name.] The lower number of a 

 fraction which shows into how many parts 

 the unit is divided. 



Densimeter, ( den-sim'e-ter ). [L. densus, 

 thick ; metrum, measure.] An apparatus 

 for measuring the specific gravity of liquids. 



Density, (den'si-ti). [L. densus, thick.]= 

 Specific gravity. D. ofelectricity=Ia.tQusity 

 ofE. 



Dental formulae, I? C PM M J I=Incisors; 

 C=Canines; P.M=Premolars; M=Molars; 

 - expresses the number of each kind of teeth 

 on each side of each jaw. D prefixed to each 

 expresses the deciduous or first set of teeth. 



Dentalidae, (den-tal'i-de)=Tooth-shells. 



Dentalina, (den-tal'i-na). [Dim. of L. dens, 

 tooth.] A small gasteropod. 



Dentalium. (den-ta'li-um). [L. dem, tooth.] 

 =Tooth-shell : a small marine molluscous 

 animal, belonging to the Pteropoda or Gas- 

 teropoda, the shell of which resembles a 

 small tusk. 



Dentaria, (den-ta'ri-a). [L. dens, tooth.]= 

 Too th-wort=; Cora.1 root : an herb, with Jarge 



purple flower, belonging to Brassicaceae, 

 named from the scales on the roots, which 

 look like teeth. 



Dentary bone, (den'ta-ri). [L. dens, tooth.] 

 The bone in Vertebrata generally, which 

 corresponds to the lower jaw in man. 



Dentate, (den'tat). [L. dentatus, having 

 teeth.]=Tooth-edged. 



Denticles, (den'ti-klz). [Dim. of L. dens, 

 tooth.] Small teeth, a number of which 

 make up the compound tooth which ia 

 found only in the Cape Ant-eater. 



Denticulate, (den-tik'u-lat). [L. denticulatus, 

 toothed.] Having fine teeth. 



Dentine, (den 'tin). [L. dens, tooth.] A 

 dense substance, resembling bone, which 

 forms the greater portion of teeth. 



Dentirostres, (den-ti-ros'trez). [L. dens, tooth; 

 rostrum, beak.] A sub-division of Inses- 

 Bores, including shrikes, warblers, thrushes, 

 and other birds having a tooth-like projec- 

 tion in the beak. 



Dentition, (den-tish'un). [L. dens, tooth.]= 

 Number and arrangement of teeth. 



Denudation, (de-nu-dfi'shun). [L. denudo, I 

 lay bare.] Removal of solid matter by 

 water or air. Aqueous D. : removal by 

 water. Subaerial D. : removal by wind, 

 rain, &c. Littoral D. : removal by water 

 between high and lower water marks. 



Deodar, (de'o-dar). [The Hindoo name.] A 

 very durable wood, the timber of an Indian 

 tree belonging to Pinaceai. D. cettar=Ced- 

 rus deodara. 



Deodorisers, (de-o-do-rl'zerz.) [L. de, from; 

 odor, smell.] Substances which cause re- 

 moval of offensive odours by causing the 

 presence of others, cf. Disinfection. 



Deoxidation, (de-oks-i-da'shun). [L. de, from; 

 Oxide, q.v.] The separation of oxygen from 

 a substance containing it, usually by means 

 of heat. 



De Pambour's theory of steam power. Av= 

 m S^-; A=Area of piston in feet; v= Velocity 

 of piston ; S=Quantity of water evaporated ; 

 P=Pressure in boiler; R=Resistance against 

 the piston; w=Ratio of steam formed to 

 water. 



Departure, (d5-par'tur). The distance which 

 a ship has gone east or west of its original 

 meridian. 



Dephlogisticated. v. Phlogiston. 



Depolarization, (de'-po-la-rl-za'shun). [L. de, 

 from ; Polarization, q.v.] The double re- 

 fraction of a ray of polarised light. 



Depressor muscles, (de-pres'sor). [L. depres- 

 sus, low.] Those used to lower the parts.to 

 which they are attached. 



Derbyshire. 2>. nec=Goitre ' an enlarge- 

 ment of the thyroid gland, causing a 

 swelling in the upper and fore part of 

 the neck ; also called Bronchocele. D. spar 

 =Blue John ; a mineral, chiefly fluoride of 

 calcium. 



Derived current. The current which passes 

 along a wire which is connected at each end 

 with a wire along which a current is already 

 passing. 



G 



