isomerous 



-lum 



members of successive cycles equal 

 in number, as the petals and sepals ; 

 Isomerog^amy {n^pos, a part ; ydjj.os, 

 marriage), the copulation of iso- 

 gametes, as in many Algae (Hait- 

 mann) ; I'somorpb (fiopcj)^, shape),, 

 shnilar in external form, l>nt not 

 in essential structure ; a mineralogi- 

 cal term;l8omorph'ism, the condition 

 described, as exemplified by the out- 

 ward agreement of purple Crocus and 

 Colchicum ; isoph'agous {(pdya, I 

 eat), applied to Fungi which attack 

 one, or several allied species (Eriks- 

 son) ; isophe'nous {(paivw, I appear), 

 used of individuals which belong to 

 the same phenotype (Johannsen) ; 

 isoph'orous {<pop4a), I carry), trans- 

 formable into something else 

 (Crozier) ; isopho'tic (cpws, (pccTos, 

 light), equally illuminated, as leaves 

 Avhich are erect, so that both sides 

 are exposed to the light (Clements) ; 

 Isopbo'tophyll {(pvkXoy, a leaf), a leaf 

 in which botli halves of the chloren- 

 chym are alike, due to equal il- 

 lumination (Clements) ; isophyrious, 



(1) leaves alike, in shape or size ; 



(2) bilateral; Isophylly, (1) the 

 condition described; (2) " biiater- 

 aiity expressed in the form of two 

 equal sides about an axis of the 

 member in the tangential plane of 

 the system " (Church) ; Isophytot'- 

 onus {(pvrov, a plant; rovos, strain), 

 in temperature identical with the 

 plant's requirements (Cler^ients) ; 

 Isoplan'ogametes {nxdvos, wander- 

 ing ; -f- Gamete), motile sexual cells 

 of equal size, occurring in Algae; 

 isopo'lar {polus, a pole), an axis of 

 Diatom frustules is so termed when 

 its extremities are similar (0. Muel- 

 ler); lBopro'tbally(4- Prothai-lus), 

 producing prothallia which are 

 similar in sexual character (Van 

 Tieghem) ; i'soschist {cxicttos, split), 

 ap})lied to a cell of a brood, all of 

 which are equal in size and function 

 (Hartog) ; isosmot'ic {w<Tfj.os, im- 

 pulse, pushing), passing by osmosis 

 in or out with eoual facility ; I'go- 

 spore {a-rropa, seea), a spore produced 



by one of the Isospo'reae, plants 

 having one kind of spore, as in 

 Ferns, opposed to heterosporous ; 

 isos'porous, homosporous, or having 

 one kind of spore only ; Isosp'ory, 

 the state of producing one sort of 

 spore; isoste'monous, -nus, having 

 as many stamens as petals, or sepals ; 

 Isoste'mony, ecpiality in number of 

 staniens with the segments of the 

 perianth whorls ; isos'tic, Van Tieg- 

 hem's term when the mother root 

 has more than two xylem bundles ; 

 I'sotherel&e'pos, summer)', an isotherm 

 of the hottest months (Boulger) ; 

 isotonic {rovos, a strand, a brace) 

 Concentra'tion, that degree of differ- 

 ent solutions in which they attract 

 water with equal force (De Vries) ; 

 iso»'tomous ((TTOfxa, a mouth), the 

 calyx and corolla the same size ; 

 Isofrophy {rpo(pi], food), equal growth 

 all round : adj. isotroph'ic ; isosty'- 

 lous {+ Stylus), the styles being 

 similar, opposed to heterostylous ; 

 Isot'rophyte {Tpo<pi], food; <pvTov, 

 a ])lant), a parasitic Fungus whose 

 influence is only chemical, with but 

 slight changes in the liost (Wakkev) ; 

 isot'ropous {rpoTTos, direction), equal 

 torsion in development, as in val- 

 vate and contorted aestivation (K. 

 Schumann) ; Isot'ropy, capable of 

 being attracted in any direction ; 

 I'sotype {tvttos, a type), forms 

 common to different countiies ; 

 isotyp'tc, described from more than 

 one species, all of which ai^e 

 congeneric. 



Isth'mus {la-dfxbs, a neck of land), (1) 

 the narrowed connection between 

 half-cells of Desmids; (2) the girdle 

 of such Diatoms as IsUnnia. 



itera'to-proiif'erous (/i!6ra/«s, repeated ; 

 -f- ruoLiFEKOu.s), repeatedly bearing 

 prolifications. 



Iteorogy (ire'a, a willow ; \6yos, dis- 

 course), the study of the genus 

 JSalix, willows; adj. iteolog'ic. 



ithyphyHus {Ms, straight ; <pv\\ov, a 

 leaf), straight and stitf-leaved.' 



-ium (-etov, locative affix), suffix de- 

 noting a formation (Clements). 



204 



