MORPHOLOGY, OR COMPARATIVE ANATOMY. 



The details regarding coherence will be treated of more conveniently 

 in the chapters on the separate organs. 



Adhesion may exist between the inner and outer circles of the 

 floral envelopes, between petals and stamens, and between stamens 

 and pistils, also between calyx, corolla and stamens with pistil 

 free ; or the calyx, corolla, and stamens may all adhere to the pistil. 

 No case is known of adhesion of the three inner circles with a free 

 calyx. 



What is commonly termed adhesion is, as before explained, more strictly 

 want of separation between parts which ordinarily become detached one 

 from the other during growth. 



Insertion. The point of emergence of an organ is inappropri- 

 ately called its insertion ; and when an organ is not adherent to 

 any other circle, but emerges directly from the receptacle, it is said 

 to be free. 



When the outer organs spring from the receptacle, they are called 

 hypogynous (fig. 168), signifying below the pistil ; if the stamens appear 

 to adhere to the free tube of the .calyx or corolla, they are said to be 



Fig. 169. 



Fig. 168. 



Fig. 168. Hypogynous flower of Ranunculus, in section. 

 Fig. 169. Perigynous flower of Prunus, in section. 



perigynous (fig. 169) ; while if the tube of the calyx or receptacle is 

 carried up and adherent to the sides of the pistil, the stamens become 

 apparently inserted on the top of the ovary, and are then called epigynous 

 (fig. 170). 



Some other terms are used in reference to the insertion of the petals 

 and stamens : thus, thalamifloral, or emerging from the receptacle, is 

 synonymous witlh hypogynous (fig. 168) ; calycifloral, indicating emer- 

 gence from the throat of the calyx, may agree with either the perigynous 

 (fig. 169) or epigynous (fig. 170) conditions; while corollifloral, emer- 

 gence from the tube of the corolla, is a form of the perigynous insertion. 



The terms inferior and superior are occasionally applied to the calyx, 

 according as it is free (fig. 168) or adherent (fig. 170) to the pistil all the 

 way up; occasionally it is half-superior (Saxifraga^ fig. 171). The same 

 terms are also applied to the .pistil in the reversed sense to indicate the 



