HEDERACE.2E 



160 



HELIOTROPISM 



plant, the type of Hederaceae. H. Jielix 



tvy. 

 Hederacese, ( hed-er-5,'se-S ). [Hedera, q.v.] 



Ivy, &c. = Araliacese, q.v. 

 Hederic acid, (hed'er-ik). [Hedera, q.v.} An 



acid obtained from the seeds of Ivy. 

 Hedge, (hej). [Hege, the A.-S. word.] H. 



/iO#=Erinaceus. H. 



Hedgehog. 



Pi 



Iv 



formis. H. mustard 



= Sisymbrium. H, 



parsley = Torilis : a 



sub-genus of Caucalis. 



H. sparrow, v. Spar- 



row. 

 Hedraeophthalmata, 



(hed-re-of-thal'ma-ta). [Gk. hedraios, sessile 



ophthalmos, eye. ]=Hedneopthalmia. 

 Hedraeophthalmia, (hed-re-of-thal'mi-a). [Gk. 



hedraios, sessile ; opthalmos, eye. ] A division 



of Crustacese, including those having sessile 



eyes=Edriophthalmia, q.v. 

 Hedyotis, (he-di-5'tis). [Gk. hedys, sweet; ous, 



ear .]= Ear-wort: a plant belonging to Cin- 



chonacese. 

 Hedyphane, (he'di-fan). [Gk. hfdys, sweet; 



phaino, I shine.] A mineral, chiefly oxide 



of lead and calcium. 

 Hedysarum, (he-dis'a-mm). [Gk. Jiedysaron, 



sweet-smelling.] A plant belonging to Legu- 



ruinaceae. H. coro7iarium=French honey- 



suckle. H. gr?/ra?is=Moving saintfoin. 

 Heel, (hel). [The A.-S. word.] The hinder 



portion of the foot. 

 Height, measurement of. 1. By Trigonometry, 



q.v. 2. By barometer, q.v. 3. By boiling 



point of water, v. Boiling. 

 Heisch's test for sewage in water. The 



addition of granulated sugar and exposure 



for several hours to light, causing the 



presence of a fungus if there be any 



sewage. 

 Helamys, (hel'a-mys). [Gk. helios, fawn;m.'/, 



rat.] A rat-like animal, resembling the 



jerboa; also called Pedetes, belonging to 



Rodentia. H. cape?ms:=Jumping hare. 

 Helarctos, (hel-ark'tos). [Gk. hellos, fawn; 



arctos, bear.] A variety of the bear. v. 



Ursus. H. Malayanus = Malay bear. H. 



euryspilws=Bornean bear. 

 Helcura, (hel-ku'ra). [Gk. helho, I drag; ourn, 



tail.] A tortoise-like animal, known only 



by fossil tracks, v. Lithichnozoa. 

 Helen's (St.) series. [St. Helen's, in the Isle 



of Wight.]=Osborne series, q. v. 

 Helenin, (hel'e-nin)c=C 16 H 14 5 : a crystalline 



substance obtained from the plant Inula 



helenium. 

 Heliacal, (he-li'a-kal). [Gk. helial-ost, belong- 



ing to the sun.] Closely connected with the 



sun; used of a star which is seen near the 



sun. 

 Helianthemum, ( he-li-an'the-mum ). [Gk. 



helios, sun; anthemon, flower. ]= Rock-rose 



= Sun-rose: a plant belonging to Cistacere. 

 Helianthoid, (he-li-an'thoid). [Helianthus, 



q.v.; Gk. eidos, form.] Resembling the sun- 



flower. H. p<%pes=Zoantharia. 

 Helianthus, (he-li-an'thus). 'Gk. helios. sun; 



anlhos, flower. ]=Sun-flower; a plant belong- 

 ing to Asteracese. 



Helichrysum, ( hS-lik-ri'sum ). [Gk. helios, 

 sun; chrysos, gold.] Everlasting flower: a 

 plant belonging to Asteracese. 



Helicidse, (he-lis'i-de). [Helix, q.v.] Snails: 

 a family of molluscous animals belonging to 

 Gasteropoda. 



Helicin, (hel'i-sin). C 13 H 16 O 7 : a crystalline 

 substance obtained from salicin. 



Helicoidal, (he-li-koi'dal). [Helix, q.v.; Gk. 

 eidos, form.] Spiral. 



Helicoidea, (he-li-koi'de-a). [Helix, q.v.; Gk. 

 eidos, form.] A division of Foraminifera, 

 including those whose segments are in a 

 spiral form. 



Helicoidin.(hel-i-koi'din)=(C 26 H 3 4O]4)._>3lToO: 

 a crystalline substance obtained from salicin. 



Heliconii, (he-li-ko'ni-I). [Gk. helios, sun.] 

 A family of butterflies: not eaten, by birds 

 nor by monkeys. 



Heliocentric, (he-li-o-sen'trik). [Gk. Jiclios, 

 sun; kentron, centre.] Having the suu as 

 centre. 



Heliography, (he-li-og'ra-fi). [Gk. helios, sun; 

 grapho, I write.] 1. A description of the 

 sun. 2.= Photography. 



Heliolites, (h-li-6-li'tez). [Helix, q.v.; Gk. 

 lithos, stone. ] . Fossil remains of corals, 

 many species of wnich are found in Devonian 

 and Silurian rocks: have beautiful cceuen- 

 chyma. 



Heliomaster, (lu'-li-o-mas'ter). [Gk. helios, 

 sun. ] A humming-bird of Nicaragua. 



Heliometer. (he-li-om'e-ter). [Gk. helios, sun ; 

 metron, measure.] A telescope adapted to 

 the measurement of small angular distances, 

 named from being used to me;isure the dia- 

 meter of the sun. 



Heliometric method of observing transit, v. 

 Transit. 



Heliopora, (h("-li-op'o-ra). [Gk. helios, nun.] 

 A round-shaped coral reef polype of indigo- 

 blue colour. 



Helioscope, (he'li-os-kop). [Gk. helios, sun; 

 tko} fo, I see.] An instrument for observing 

 the sun. 



Heliostat, (hG'li-o-stat). [Gk. helios, sun; 

 statos, fixed.] A mirror used to reflect sun- 

 light, with machinery to move it as the sun 

 moves, so as to keep the ray stationary. 



Heliotrope, (he'li-6-trop).) [Gk. helios, sun, 

 trope, turning. 1. A plant belonging to 

 Ehretiaceau: also called Turnsole=Heliotro- 

 pium. 2. A stone coloured green and red. 

 also called jasper bloodstone=drops of jasper 

 in quartz. 3. An instrument for reflecting 

 light as signals. 



Heliotropic, (he-li-o-tro'pik). [Gk. heH&8, sun ; 

 trope, turning.] Bending under the influence 

 of light. 



HeliotropicesB, ( he-li-o-tro-pis'e-C ). [Helio- 

 tropium, g.v.]=Ehretiacese, q.v. 



Heliotropism, (he-li-o-tro'pizm). [Gk. helios, 

 sun; trope, turning.] The tendency to turn 

 towards the sun; positive in most stems of 

 plants, negative in tendrils, root-hairs, &c. ; 

 the higher rays of light, blue, violet, and in- 

 digo, cause a less degree of growth on one side. 



