92 FLOWERS. 



SECTION IV. 



FLOWERS AND FLOWERING TOPS 



The anatomical characters presented by powdered flowers and 

 flowering tops will depend in the first place upon the number of 

 different organs that are present in the drug. If the latter con- 

 sists simply of petals the chief diagnostic characters will be 

 found in the shape of the stomata, and in the papillae which are 

 generally met with on the surface of these delicate organs. 

 Some petals are furnished with simple and glandular hairs in 

 which case these, of course, may be utilised in establishing the 

 identity of the powder. By such means as these the presence 

 of calendula florets in powdered saffron may be detected; the 

 former bear pluriserial hairs near the base of the corolla, and 

 these are easily recognised in the powdered drug. The presence 

 of secretory ducts may also sometimes be of service in deter- 

 mining adulteration, as for instance that of saffron with 

 safflower, for the florets of the latter contain oleo-resin ducts 

 that can be detected in the powdered drug. 



Pollen grains are also often present on the corolla of the 

 flower, and their presence, shape and size may afford informa- 

 tion that should not be under-estimated. The pollen grains of 

 the saffron-crocus are of considerable size and nearly smooth, 

 whilst those of composite plants are usually furnished with 

 numerous spiny projections. An abundance of pollen grains in 

 powdered cousso indicates the presence of the staminate in- 

 florescence which is inactive, and is excluded from official use. 



