238 



OBGANOGKAPHY. 



seen by making a transverse section as shown \nfig. 499. Tlius 

 here we observe two parallel lohes, b, b, separated by a portion, 

 A, a, called the connective, to which the filament is attached. 



Fig. 500. 



Fig. 501. Fig. 502. 



Fig. 503. 



Fig. 500. Quadrllocular anther of tbe Flowering 

 Rush (Butomus umhellatus). a. Filament bear- 

 ing an entire anther, h. Section of the anther 



with its four loculi. i^^ifir. 501. Androeciura of 



Milkwort {Polygala), with one-celled anthers 



dehiscing at their apex. Fig. 502. One of the 



stamens of the Lady's Mantle (Alchemilla). 

 The anther is unilocular or one-celled, and de- 

 hisces transversely. 



Each lobe is divided into two cavities, d, d, 

 d, d, by a septum which passes from the 

 connective to the walls of the anther. The 

 cavities thus formed in the lobes of the 

 anther are called cells, loculi, or theccB. All 

 anthers in an early stage of development 

 possess, as we have just seen, four loculi, 

 and this is considered the normal state. 

 When a fully developed anther exhibits a 

 similar structure, as in the Flowering Eush 

 (Buto7nus umhellatus), it is four-celled, 

 quadrllocular, or tetratheccd {fig. 500) ; or 

 when, as is more commonly the case, the 

 partitions separating the two loculi of each 

 anther-lobe become absorbed, it is two-celled, 

 hilocular, or dithecal {fig. 488). In rare cases, 

 the anther is unilocular or one-celled, as in 

 the Mallow, Milkwort {fig. 501), and 

 _. Lady's Mantle {fig. 502): this arises, either 



The^Sage. ^/^Piia- from the abortion of one lobe of the an- 

 hetri^n '^' a?"on^^"7d ^^®^' ^^^ *^® absorption of the septum 

 a loc'uius V, contain- between the two cells of the lobe, that is 

 is laid to'be^fSie^ present ; or by the destruction of the par- 

 and at the other end tition wall of the two lobes as well as of the 

 a locuius Is without ggpta between the cells of each lobe. In 

 pollen, in which case ^ , ^ . . • ^ 



it is sterile. some plants again, as m many species of 



Salvia, the connective becomes elongated 

 into a kind of stalk, each end of which bears an anther lobe 

 {fig. 503), in which case there appear to be two uniloculctr or 

 one-celled anthers. When this occurs one lobe only, //, contains 

 pollen, the other, Is, is sterile. 



