THE ASCLEPIAS TRIBE. 185 



the seed-vessel is ripe, that it consists of two, dry, 

 tough cases, opening by the face, and placed almost at 

 rififht angles with each other, so that the seed-vessels 

 and stalk together, form the figure T. But it often 

 happens that one ovary shrivels up and disappears ; 

 in that case, the other gi'ows upright upon its stalk 

 {Jig. 10.), as is usual in other plants. In the inside 

 of the seed-vessel is a large number of fiat, brown 

 seeds, terminated by a delicate silk tuft {Jig. 10.), and 

 containing a thin, flat embryo, without any albumen 

 ifig.ll.). 



It must be quite plain to you, that at least three 

 circumstances will separately characterise the Ascle- 

 pias Tribe ; for no other Monopetalous order has 

 either, 1. the pollen adhering into bags, or, 2. the 

 anthers adhering firmly to a stigma-like table, or, 3. 

 the corolla augmented by a coronet, or second row of 

 petals. 



You must not, however, expect that all the tribe will 

 agree in the nature of their coronet ; some have only 

 a single row of secondary petals, as the plant now 

 before you, others have two or even three rows, in 

 various states of combination or developement. For 

 the purpose of studying these matters, you should 

 examine the curious speckled flowers of the Stapelia^ 

 and the honey-dropping, waxen blossoms of the Hoya. 

 The former, indeed, will generally repel you by their 

 intolerable smell, if you wait till they are naturally 

 expanded ; but if you cut them open some days pre- 

 viously, you can examine them without inconvenience. 



Cgnanchum and Periploca, arc other common genera 



