Yi OUTLINES OF BOTANY. 



43. The teeth, lobes, segments, or leaflets, may be again toothed, If^f^' ^^7','^^'^' . ™ 

 compounded. Some leaves are even three or more times divided or compounded, in tne laiier 

 case they are termed decompound. When twice or thrice pinnate {bipmnate or tnpmnate}, eaon 

 primary or secondary division, with the leaflets it comprises, is called a pmtia. When tne pinna 

 of a leaf or the leaflets of a pinna are in pairs, without an odd terminal pinna or leaflet, tne leai 

 or pinna so divided is said to be abruptly pinnate ; if there is an odd terminal pinna or leanei, 

 the leaf or pinna is unequally pinnate (imparipinnatuvi) . . . 



44. The number of leaves or their parts is expressed adjectlvely by the following numerals, 



derived from the Latin : — 



uni-, bi-, tri-, quadri-, quinque-, sex-, septem-, ooto-, novem-, decern-, raulti- 

 1-, 2-, 3-, 4-, 6-, 6-, 7-, 8-, 9-, 10-, many- 



prefixed to a termination indicating the particular kind of part referred to. Thus-— 



unidentate, bidentate, multidentate, mean one-toothed, two-toothed, many-toothed, etc. 



bifid, trifid, multifid, mean two-lobed, three-lobed, many-lobed, etc. 



unifoliolate, bifoUolate, multifoliolate, mean having one leaflet, two leaflets, many leaflets, etc, 



um/oliate, bifoliate, multifoliate, mean having one leaf, tWo leaves, many leaves, etc. 



bitemate and triternate, mean twice or thrice ternately divided. 



unijugate, bijugate, multijugate, etc., pinnae or leaflets, mean that there are in one, two, 



many, etc., pairs (juga). 



45. Iieaves or their parts, when flat, or any other flat organs in plants, are 



Unear, when long and narrow, at least four or five times as long as broad, falsely compared 

 to a mathematical line, for a linear leaf has always a perceptible breadth. 



lanceolate, when about three or more times as long as broad, broadest below the middle, and 

 tapering towards the summit, compared to the head of a lance. 



cuneate, when broadest above the middle, and tapering towards the base, compared to a 

 wedge with the point downwards ; when very broadly cuneate and rounded at the top, it is often 

 called ^a6eJK/oj'm oi fan-nhaped. 



spathulate, when the broad part near the top is short, and the narrow tapering part long, 

 compared to a spatula or flat ladle. 



ovate, when scarcely twice as long as broad, and rather broader below the middle, compared 

 to the longitudinal section of an egg ; obovate is the same form, with the broadest part above 

 the middle. 



orbicular, oval, oblong, elliptical, rhomboidal, etc., when compared to the corresponding 

 mathematical figures. 



transversely oblong, or oblate, when conspicuously broader than long. 



falcate, when curved like the blade of a scythe. 



46. Intermediate forms between any two of the above are expressed by combining two terms. 

 Thus, a linear-lanceolate leaf is long and narrow, yet broader below the middle, and tapering to 

 a point ; a linear-oblong one is scarcely narrow enough to be called linear, yet too narrow to be 

 strictly oblong, and does not conspicuously taper either towards the summit or towards the base. 



47. The apex or summit of a leaf is 



acute or pointed, when it forms an acute angle or tapers to a point. 



obtuse or blunt, when it forms a very obtuse angle, or more generally when it is more or less 

 rounded at the top. 



acuminate or cuspidate, when suddenly narrowed at the top, and then more or less prolonged 

 into an acumen or point, which may be acute or obtuse, linear or tapering. Some botanists 

 make a slight difference between the acuminate and cuspidate apex, the acumen being more 

 distinct from the rest of the leaf in the latter case than in the former ; but in general the two 

 terms are used in the same sense, some preferring the one and some the other. 



truncate, when the end is cut off square. 



retuse, when very obtuse or truncate, and slightly indented. 



emarginate or notched, when more decidedly indented at the end of the midrib ; obcordate, if 

 at the same time approaching the shape of a heart with its point downwards. 



mucronate. when the midrib is produced beyond the apex in the form of a small point. 



aristate, when the point is fine like a hair. 



48. The base of the leaf is liable to the same variations of form as the apex, but the terms 

 more commonly used are tapering or narrowed for acute and acuminate, rounded for obtuse, and 

 cordate for emarginate. In all cases the petiole or point of attachment prevent any such 

 absolute termination at the base as at the apex. 



49. A leaf may be cordate at the base whatever be its length or breadth, or whatever the shape 

 of the two lateral lobes, called auricles (or little ears), formed by the indenture or notch, but the 

 term cordiform or heart-shaped leaf is restricted to an ovate and acute leaf, cordate at the base, 

 with rounded auricles. The word auricles is more particularly used as applied to sessile and 

 stem-clasping leaves. 



50. If the auricles are pointed, the leaf is more particularly called auriculate ; it is moreover 

 said to be sagittate, when the points are directed downwards, compared to an arrow-head ; 

 hastate, when the points diverge horizontally, compared to a halbert. 



.51. A renifm-m leaf is broader than long, slightly but broadly cordate at the base, with rounded 

 auricles, compared to a kidney. 



