FORMS OF OVULES 81 



The Anatropous Ociilc. — An anatropous ovule (Fig. 242) is one tlie 

 body of which is completely inverted. The raphe runs its entire length 

 and the micropyle is brought close to the hiluni, while the chalaza is 

 at the opposite end. 



TJw Amphitropous Oeule. — An amphitro])ous ()vule (Fig. 243) is one 

 which is i)artly inverted, occupying a position more or less at right 

 angles with its funiculus. Its raphe runs only part of its length, and the 

 hilum is at some point intermediate between the chalaza and micro- 

 pyle, which are at opposite ends. 



The CampyJotropom Omde. — A campylotropous ovule (Fig, 244) 

 is one which need not be at all inverted, but the body of which is 

 doubled over so as to bring the micropyle down near the chalaza. It 

 has, of course, no raphe, and the hilum and chalaza are one. It is very 

 difficult to distinguish this form from an anatropous ovule with a very 

 broad raphe. 



The Atropous or Orthotropoiis Omde. — This (Fig. 241) is an ovule 

 which is neither doubled nor turned, the body being straight and erect 

 upon the funiculus, and having no raphe, the hilum and chalaza at 

 one, and the micropyle at the opposite end. 



Before proceeding to the subject of pollination and fertilization and 

 the changes in the several parts of the flower consequent thereon, we 

 must consider in detail the torus and its modifications. 



