dje Crcatfurj) of 3S0tanj?, 



624 



INTERRUPTED. When any symmetri- 

 cal arrangement is destroyed l>y local 

 causes: a leaf is interruptedly pinnated 

 when some of the pinnae are much smaller 

 than the others, or wholly wanting. 



INTERVENIUM. The space of paren- 

 chyma between the veins. 



INTEXINE. That coating of the rollen 

 which is next the extine or outer crust, 

 and above the intine or inner lining. 



INTINE. The innermost lining of the 

 shell of a pollen grain. 



INTORTUS. Twisted upon itself. 



INTRA. Placed within anything ; as in- 

 trafohaceus, placed within the axil of a 

 leaf. 



INTRARIUS. Turned inwards ; that is 

 to say, towards the centre of a flower 



INTRAVALVULAR. Placed within 

 valves, as the dissepiments of many cru- 

 cifers. 



INTRICATE. Entangled. 



INTROCURVITS, INTROFLEXUS, IN" 

 TROPLEXED. Curved inwards. 



INTRORSE. Turned towards the axis 

 to which it appertains; as an anther when 

 its valves face the centre of a flower. 



INTROVENIUM. Hidden-veined ; when 

 veins are so much buried in parenchyma 

 that they are not visible on external in- 

 spection. 



INTRUSUS. Pushed inwards ; as when 

 the base of a fruit is so concave as to seem 

 as if pushed inwards by the peduncle. 



INULA. A genus of composite plants, 

 having the outer or ray florets strap-shaped 

 and containing pistils only, while the 

 central florets are tubular and contain 

 both pistils and stamens ; the anthers have 

 two bristles at their base : the pappus con- 

 sists of rather rough hairs, arranged in a 

 single row, and the involucre consists of 

 numerous overlapping scales, but the recep- 

 tacle is devoid of scales. The species are 

 numerous and occur throughout Europe 

 and central Asia. I. Helenium, Elecampane, 

 occurs spontaneously in this country, but 

 having long been cultivated in herb gar- 

 dens, it is considered that it may origin- 

 ally have been derived from such a source. 

 It is a perennial plant with a stem from 

 three to five feet high : large saw-toothed 

 leaves tapering to a stalk, the upper ones 

 smaller, and embracing the stem ; and large 

 heads of yellow flowers. The root has an 

 aromatic camphor-like taste, due to the 

 presence of a crystalline substance called 

 helenin, allied in chemical constitution to 

 creosote. It also contains a quantity of 

 starchy material, called inulin, which dif- 

 fers from ordinary starch in being coloured 

 yellow by iodine. Elecampane was for- 

 merly much used as an aromatic tonic, 

 and as a stimulant of all the secreting 

 organs, likewise in coughs, dyspepsia, &c. 

 I I. Conyza, a common hedge plant in some 



parts of England, grows to the height of 

 two to three feet, and has rough leaves, 

 and numerous small flower-heads disposed 

 in a corymb This plant, called Plough- 

 man's Spikenard, has a somewhat aromatic 

 odour. Its leaves are occasionally gather- 

 ed in place of those of Digitalis, from 

 which they may be distinguished by their 

 roughness and their smell. [M, T. M.] 



INPNCANS. Said of surfaces covered 

 with little hooked hairs, as the leaves of 

 some species of Galium. 



INUNDATE. Flooded. Sometimes co- 

 vered with water, sometimes dry. 



INUS. A termination expressing the 

 quality of resemblance, as calycinus, like 

 a calyx in position, in colour, &c. ; it also 

 | expresses augmentation, as calycinus, hav- 

 ing a large calyx. 



INVERTED. Having the apex in an 



opposite direction to that of some other 

 thing; as many seeds. 



TNVERTENTIA FOLIA. Leaflets which 

 in their sleep hang downwards, but touch 

 by their upper surfaces. 



INVOLUCEL, INVOLUCELLUM. A di- 

 minutive involucre; a secondary invo- 

 lucre usually not containing more than one 

 or two flowers. 



INVOLUCRAL. Of or belonging to an 

 involucre. 



INVOLUCRATE. Having an involucre. 



INVOLUCRE, INVOLUCRUM. A ring 

 or rings of bracts surrounding several flow- 

 ers. Also the peridium, volva, or annulus 

 of some fungals. Also the cup-formed 

 external indusia of some ferns. 



INVOLUCRARIA. A genus of CucurM- 

 tacece, consisting chiefly of Indian species, 

 nearly allied to Tric.hosanthes, but having 

 the segments of the corolla entire, and the 

 bracts of the racemes of male flowers large, 

 leafy, concealing the flowers before their 

 expansion. [M. T. M.] 



INVOLUTE, INVOLUTIVE. When 

 edges are rolled inwards on each side, as 

 the leaf of the apple. 



IOCHROMA. A genus of South Ameri- 

 can shrubs belonging to the Solanacecr, de- 

 riving its name from the handsome violet 



I or purple-coloured flowers. The calyx is 

 tubular, somewhat distended, with five un- 



| equal teeth, and becomes larger as the 

 fruit ripens. The corolla is tubular, much 

 longer than the calyx, and conceals the 

 stamens. The fruit is succulent, two- 



[ celled, many-seeded, and enclosed within 



! the bladdery calyx. /. tubulosum and I. 



' lanceolatum are handsome greenhouse 

 shrubs. [M. T. MJ 



IODINA. A genus of Olacacece, a South 

 American shrub with rhomboid leathery 

 leaves, spinous at the angles and apex, and 

 subsessile flowers in axillary glomerules, 

 having a five-cleft calyx, five petals on a 



