390 MOKPHOLOGY. 



bud-integument (integumentum secundum externum, testa [Robert 

 Brown, Brongniart], primine [Mirbel]). Then the orifice of the outer 

 integument is known as the exostome (exostomium), that of the inner as 

 the endostome (endostomium). If beneath the entire seed-bud there 

 yet remains a free, distinguishable piece of the axis, this is termed the 

 gemmophore (funiculus). The seed-bud is found in this state of 

 development in, for example, Hydrocharidea, with the exception of 

 Stratiotes, in many Aracece, in the Polygonacece, &c. 



This form of seed-bud is modified in many ways by means of the 

 curvatures above mentioned. 



1. The funiculus is much elongated, the nuclear papilla bends 

 downwards, and thus the side either of the naked nucleus or of the 

 simple or of the external bud-integument turned towards the funi- 

 culus, becomes gradually blended with it. In the perfect seed-bud 

 the nuclear papilla then lies close to the point of attachment, the 

 chalaza opposite to the point of attachment, and the line from the 

 centre of the chalaza through the middle of the nucleus is straight. 

 Such a seed-bud is termed re versed (gemmula anatropa]\ the adherent 

 part of the funiculus is termed the raphe. This appears to be the 

 most frequent form ; it occurs in the naked nuclei * of Hippuris and 

 fiubiacece, in the simple bud-integument of the Composite, in the 

 double bud-integument of the Liliacece, &c. 



If the blending of the funiculus with the bud-integument only 

 affects the lower part of the seed-bud, so that a considerable part of 

 the apex (the upper half) is left free, the seed-bud is said to be half 

 reversed (gemmula hemianatropa), as, for instance, in Meconostigma 

 and many Aracece. If the funiculus is then very short and scarcely 

 perceptible (g. sessilis), the seed-bud appears as if attached by the 

 centre (medio affixa, peltata). 



2. The two sides of the seed-bud are unequally developed ; one 

 remains almost totally at a stand-still, whilst the other is exceedingly 

 increased, and in the perfect seed-bud constitutes almost the entire 

 circumference of the seed-bud. The point of attachment and 

 chalaza are here almost coincident ; the nuclear papilla lies near the 

 first, and a line drawn from the centre of the chalaza through the 

 centre of the nucleus to the point of the nuclear papilla is a curved 

 line ; such a seed-bud is termed a curved seed-bud (gemmula 

 campylotropa). 



I am not acquainted with any example of this in the naked 

 nucleus. Datura may be cited as an example in the simple bud- 

 integument, and in the double bud-integument instances are offered 



* Robert Brown also enumerates the Apocynacece and Asclepiadacece here. I have already 

 said that the Apocynacece have a simple integument ; but, more recently, I have convinced 

 myself that in the Asclepiadacece, also, a very minute nucleus is enclosed in a thick 

 integument at a very early period. . Jn both families the nucleus is displaced by the 

 embryo-sac long before impregnation ; but the micropyle canal, which may be detected 

 long before the flowering period, proves beyond a doubt the existence of an integu- 

 ment. 



