dianthic 



Dichasium 



a flower of the same plant (K. 

 Pearson), 

 diaph'anous, -^is (Sta, through ; (palvo), 

 1 show), permitting the light to 

 shine through ; also written dia.- 

 PHANUs ; Diaph'ery {(p(pu}, I bear), 

 the calycine synthesis of two flowers 

 (Morren); Diaphototax'is((pa3s, light; 

 Ta|ts, order), the arrangement of 

 Oscillatoria threads at right angles 

 to incident light of optimal intensity 

 (Pieper) ; Diaphotot'ropism (+ Pho- 

 totropism), the act of self-placing 

 at right angles to incident light ; 

 adj. diaphototrop'ic ; Diaphragm 

 {(ppdaaco, I enclose), a dividing mem- 

 brane or partition, as (1) the con- 

 striction in the neck of the nucule 

 in Chara, from the inward projec- 

 tions of the segments; (2) the 

 transverse septa in the stem of 

 Equisetum or of grasses ; (3) the 

 layer separating the prothallium 

 from the cavity of the macrospore 

 in Vascular Cryjitogams; dia- 

 phyrious {(pvKKoVf a leaf) = DIA- 

 LYPJriYLLOUs; Diaph'ysis {(pvca, to 

 make grow), proliferation of the 

 inflorescence. 



di'arch (5t-, two; apxh, beginning), 

 having two protoxylem groups, used 

 of the steles of roots; diari'nus {&ppw, 

 fnale), Necker's term for diandrous. 



diaschis'tic (5ia, through; o'x'o't^s, 

 deft), applied to chromosomes when 

 they divide transversely; cf. ana- 

 scHisTic (Fanner) ; Dias'pasis 

 (o-Traoj, I tear), when the daughter- 

 nuclei in amitosis are torn asunder 

 (Wasielewski). 



Di'astase {Sidaraais, standing apart), 

 an amylolytic enzyme which con- 

 verts starch into malt-sugar ; -^ 

 of Transloca'tion attacks starch 

 grains gradually over their whole 

 surface; it is almost universally dis- 

 tributed in ])lants; -- of Secre'tion. 

 acts by corrosion, attacking parts of 

 the starcli -grain iirst ; it is formed 

 by the glandular epithelium of the 

 scutel.iuu of grasses ; adj. diastat'ic 



Di'aster {hi-, two ; aarrjp, a star), sop 

 Uyasteu. 



Diast^ole {diaa-Tokh, separation), the 

 slow dilation of a contractile vesicle ; 

 cf. Systole. 



Diatherm'ancy (5ta, through ; depjiaivu^ 

 I warm), the relative conductivity 

 of a medium with regard to the 

 transmission of heat (T. W. Engel- 

 mann); diathermotrop'ic { + thermo- 

 TROPic) unaffected by or placing itself 

 transversely to the source of heat ; 

 Diathermot'ropism, the condition 

 described. 



Diatme'sis (T/iT^o-ts, a cut), in Amitosis 

 when the daughter-nuclei become 

 neatly divided (Wasielewski). 



diatoma'ceous, resembling or conoist- 

 ing of diatoms whose type is Dia- 

 toma ; Diat'omine, the colouring 

 matter of Diatoms, phycoxanthine ; 

 Diat'omist, one devoted to the study 

 of Diatoms ; Biat'ompMle (</)i\ew, 

 I love), an enthusiastic student of 

 Diatoms. 



diatrop'ic (5m, through ; rpSiros, twin- 

 ing), used of organs which place 

 themselves transversely to the 

 operating force ; Diat'ropism is the 

 condition ; it may be geotp.opic or 



HELIOTROPIC. 



dibot'ryal = dibotryoid. 



dibot'ryoid(5ls, double ; -f botryoid), a 

 compound inflorescence, the branches 

 of the first and succeeding orders 

 being botryoid, such as the com- 

 pound umbel, panicle, or spike ; 

 Dicar'otin (5ls, twice, -f Carotin), a 

 lipochrome pigment; dicarp'ellary 

 (/i-apTrbs, fruit), composed of two 

 carpels or pistil-leaves ; Dicar'yocyte 

 (napvov, a nut ; kvtos, a hollow 

 vessel), a binuclente cell (Moreau) ; 

 Dicar'yoji, the complex of two inde- 

 pendent nuclei, united in the same 

 cell (Bonnet); Dicar'yophase (<pa(r«s, 

 a phase), the stage ending in the 

 ])rodartion of teleutospores (Moreau). 



dicha'sial {5ixdC(o, I disunite), re- 

 lating to a DiCHAsiuN^; ~ Cymes, 

 cymes whose secondary members 

 are dichasia, such as occur in 

 Euphorbiacea^ ; Dicha'sium, a false 

 dicliotomy in which two lateral 

 shoots of nearly equal strength 



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