inuncana 



Irritability 



inun'cans J (Lat., hooking), the surface 

 covered with glochidia or hooked 

 hairs. 



inunda'tal (inundatus, overflowed), 

 Watson's expression for those 

 plants which grow in places liable 

 to be inundated in wet weather, 

 but dry in summer ; inunda'tus, 

 flooded, sometimes under water, 

 sometimes dry. 



-inus, a Latin suffix, meaning, (1) 

 resemblance ; (2) augmentation. 



invag'inated (in, into ; vagina, a 

 sheath), enclosed in a sheath. 



inverse' (inversus, turned about), in- 

 verted ; Inver'sion, (1) a change of 

 order or place ; the action of In- 

 vertase ; (2) In'vert- en'zyme, In'- 

 vertase, an unorganised ferment, 

 which transmutes cane-sugar into 

 inverted-sugar ; inver'ted, having 

 the apex in an opposite direction 

 to the normal ; Inver'ted-su'gar, a 

 mixture of fructose and glucose by 

 the action of invertase on cane- 

 sugar ; ~ Superposition, the position 

 of accessory buds below the princi- 

 pal bud, or one first formed (Crozier) ; 

 inver'tens (Lat.), inverting, becom- 

 ing reversed, as inverten'tia Fo'lia, 

 leaves which in sleep hang down- 

 ward, but touch by the upper sur- 

 face, as in Cassia ; In'vertin = 

 INVERTASE ; this form is chiefly 

 employed by zoologists, 



invisible (invmb'&is, not to be seen), 

 used of any organ which is not 

 sufficiently developed to be seen. 

 vol'ucel, Involucdlmn (Fr. , involu- 

 celle, from involucrum, a wrapper), 

 a secondary partial involucre ; 

 involucel'late, involucetla'tus, pro- 

 vided with a secondary involucre ; 

 involu'cral, involucra'lis, belonging 

 to an involucre ; Invol'ucrate, In- 

 volucra'tus ; involu'cred, having an 

 involucre of some kind ; Involu'cre, 

 Involu'crum, (1) a ring of bracts 

 surrounding several flowers or their 

 supports, as in the heads of Compo- 

 sites, or the umbels of Umbelli- 

 ferae ; (2) the tissue of the thallus 

 in Anthoceroteae, grown up and 



overarching the embryo, afterwards 

 pierced by the lengthening sporo- 

 gonium ; (3) the peridium, volva 

 or annulus in Fungi (Lindley) ; (4) 

 the indusium of Ferns ; gen'eral~, 

 that which is at the base of a com- 

 pound umbel ; par'tial ~ , sec'ondary 

 <~ , that which surrounds a partial 

 umbel ; inrolu'cra Lig'nea, Mal- 

 pighi's name for the concentric 

 zones of growth in exogens ; In- 

 volu'cret, an involucel. 



in'volute, involu'tus, involuti'vus 

 (Lat., enwrapped), having the 

 edges of the leaves rolled inwards ; 

 Involution, (1) the act of rolling 

 inward ; (2) the return of an organ 

 or tissue to its original state ; ~ 

 Form, a swollen bladder-like form 

 of Schizomycetes, supposed to be 

 a diseased condition of the form 

 associated with it ; ~ Pe'riod, the 

 resting period ; ~ Spore, a rest- 

 ing-spore ; ~ Stage, the resting 

 stage. 



invol'vens (Lat.), rolling together, as 

 involven'tia Fo'lia used by De Can- 

 dolle, for trifoliate leaves whose 

 leaflets rise up, unite at the summit 

 ... so as to form an arch which 

 shelters the flowers, as in Trifolium 

 incarnatum, Linn. (Lindley). 



io'des (i'wc>?7S, violet-coloured), iodi'nus, 

 violet ; I'odine, an elementary body 

 obtained from marine Algae, etc.; 

 io'nides, violet-coloured. 



irreg'ular, irrerjula'ris (Late Lat., not 

 according to rule), (1) wanting in 

 regularity of form; (2) asymmetric, 

 as a flower which cannot be halved 

 in any plane, or one which is 

 capable of bisection in one plane 

 only, zygomorphic ; < Pelorla, 

 a monstrosity by which irregular 

 form has become regular by sym- 

 metric development ; Irregularity, 

 Irregular' 'itas, the state of being 

 unequal in form. 



Irritability (irritabilis, easily ex- 

 cited), phenomena induced by 

 stimuli, such as shock, absence 

 or presence of light, warmth, 

 gravity, etc. 



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