THE OVULE. 



299 



the direction of parts occurs during growth ; but the base or chalaza 

 (Fig. 626, c) is manifestly the point of attachment, the orifice (/) 

 is at the opposite end, and the ovule is straight and symmetrical. 



567. The Campylotropous Ovule (Fig. 525, 527) is one which grows 

 unequally, and consequently curves upon itself, so as to bring the 

 apex round to the vicinity of the base, the chalaza (c) and the orifice 

 (_/") being at length brought nearly into contact at the point of at- 

 tachment. Campylotropous or curved ovules are found in the Mig- 

 nonette, in all Cruciferous and Caiyophyllaceous plants, and in many 

 others. 



568. The Anatropous Ovule (Fig. 517, 519, 523, 524, 529) is far 

 the most common form. It is best described by likening it to an 

 orthotropous ovule which as it grew had inverted itself on its funicu- 

 lus or support, so that, while the body remains straight, its orifice or 

 apex is brought down to the funiculus and points to the placenta, 

 while the chalaza occupies the apparent or geometrical apex, i. e. the 

 summit or point directly opposite the place of attachment. The 

 ovule, thus inverted on its support, coheres with it for its 

 whole length, and accordingly has a ridge or cord, more 

 or less manifest, along one side (Fig, 529, r), connect- 

 ing the hilum, or place of attachment, and where the 

 seed separates from its insertion (h), with the chalaza (c). 

 This cord or ridge, which morphologically is merely a 

 continuation of the stalk or support of the ovule adhe- 

 rent to its face on one side, or incorporated with it, is 

 called the Ehaphe. It is a distinguishing mark of an 

 anatropous ovule, which is also recognizable by its sso 

 being straight and by having the orifice close to the point of attach- 

 ment. The rhaphe itself is often so incorporated with the coat of 



FIG. 526. Orthotropous OTUle of Buckwheat : c, hilum and chalaza ; /, orifice. 

 FIG. 527. Campylotropous ovule of a Chickweed : c, hilum and chalaza ; /, orifice. 

 riG. 528. Amphitropous ovule of Mallow : /, orifice ; h, hilum ; r, rhaphe } c, chalaza. 

 FIG 529. Anatropous ovule of a Violet ; the parts lettered as in the last. 

 FIG. 530. Vertical section of a pistil of Magnolia Umbrella, from a young flower-bud, mag- 

 nified, showing the forming ovule^ here a simple protuberance. 



