THE ARUM FAMILY. 147 



A comparative study should be made of such other 

 aroids as can be procured, e.g. sweet-flag, water-arum, etc. 

 Aside from the peculiarities of their inflorescence, which 

 mark them as a unique group, the acrid properties of 

 many members of this family constitute a marked feature. 1 



1 Miiller, Fertilization of Flowers, pp. 562-565, should be consulted. 

 Some interesting facts and suggestions are given by Allen, Flowers and 

 their Pedigrees, pp. 236-266. Certain peculiarities of fruits and seeds 

 may be looked for as different genera are examined, such as 



1. The gelatinous outer surface of the fruit of Peltandra. 



2. The seeds, albuminous in some genera and exalbuminous in 

 others. 



3. The embryo, green in a number of genera. 



