326 APPENDIX II 



(cf. Veratrum, p. 123, and Dianthus, p. 113). Sometimes both 

 male and female flowers occur on the same plant, which is then 

 termed monoecious. In other cases, specialisation is carried 

 still further, one plant bearing only male, and another only 

 female, flowers. Such plants are described as dioecious. 



Apart from the actual loss of one or other of the " essential 

 organs," there are several other directions in which flowers have 

 become modified. One of these is the union of similar members. 

 For instance, when the sepals or the petals are free from one 

 another, the flowers are called polysepalous or polypetalous, 

 but these members may unite among themselves, and then the 

 flowers are termed gamosepalous or gamopetalous. The stamens, 

 again, may unite by their filaments into a single group, when 

 they are called monadelphous, or into several groups, di-, tri-, 

 or polyadelphous. If they unite by their anthers, they are 

 spoken of as syngenesious. 



In describing the gynseceum, we took a pea-pod as a typical 

 illustration of a carpel. Many gynaecea, however, consist of 

 more than one carpel. These carpels may either be free, as in 

 the Buttercup (Text-fig. XXVL), or fused together more or less 

 completely. In the Saxifrage (Text-fig. XXVIIL), the two 

 carpels are united in the ovary region, but the styles and 

 stigmas are free ; in the Crocus (Text-fig. XXX.), the fusion has 

 gone further, and only the three stigmas are free ; while in the 

 Primula (Text-fig. V.), in which there are five carpels, they 

 are completely fused throughout. A gynaeceum consisting of 

 fused carpels is spoken of as syncarpous. 



Another way in which the flower may become modified is 

 through the union of dissimilar members. For instance, the 

 stamens, instead of growing freely from the receptacle, are 

 sometimes united for the greater part of their length with 

 the corolla (cf. Primula, Text-fig. V.). A more profound 

 modification is brought about by the hollowing out of the top 

 of the receptacle, and its union with the lower part of the 



