150 



NATURAL HISTORY OF PLANTS. 



only, or of one female flower surrounded by male flowers. But these 

 glomerules are united on a common receptacle or principal axis the 

 form of which is extremely variable in Dorstenia. It may be a circular 

 platform, flat or slightly convex or concave (fig. 112), or a cup of round 



Dorstenia multiformis. 



Fig. 110. Male bud (f). 



Dorstenia brasiliensis. 



MSB? 



Fig. 10S. Inflorescence. Fig. 109. Portion of inflorescence (f). Fig. 111. Malo flower in bloom. 



or quadrilateral contour, or unequally divided into two (fig. 108), or 

 into a greater number (fig. 113) of similar or dissimilar branches, 

 the upper surface of which is surrounded by bracts forming a 



slightly developed involucre. Most 

 frequently the receptacle is de- 

 pressed at the point of insertion of 

 the female flower into a small hol- 

 low in which the latter is encased 

 (fig. 109), whilst the surrounding 

 male flowers are inserted near the 

 margin. Dorstenias are found in 

 all the tropical regions of Africa, of 

 Asia and especially of America ; they are shrubs and, more gene- 

 rally, perennial herbs, often with very short stem. The leaves are 

 alternate, entire or more or less deeply cut, and accompanied with 

 lateral stipules, most frequently persistent and hardening on the 

 stem. Fatoiia, which closely resembles them in the organisation of 

 its flowers, is an herb of eastern Asia and the warm parts of Oceania, 

 having altogether the habit and foliage of a nettle, and the in- 

 florescence formed of androgynous cymes. Instead of being sessile, 



Fig. 112. Long. sect, of inflorescence (f). 



