FLORA OF ADEN. 
62 
Oldenlandia Schimperi. 
Acacia sp. 
Acacia Edgeworthii [pods). 
Calotropis procera. 
Acacia Edgeworthii [pods). 
Salvador a persica. 
Satvadora persica. 
Cadaba glandulosa. 
Cadaba glandulosa. 
Cadaba rotundifolia. 
Cassia sp. 
Gap par is sp. 
Cleome paradoxa [in Aden). 
Bipterygium glaucum [inland) . 
R,. Boehm has published some interesting biological notes 1 on .some 
Coleoptera of the desert fauna and their relations to the vegetation. 
Several plants are mentioned which occur also at Aden, but whether the 
corresponding insects have ever been observed J.n our area, we are not 
able to say. 
6. Colour of flowers. 
Observations on the activity of insects in the process of pollination 
would probably explain the striking curve given below. It represents 
the relative prevalence of the various colours of flowers observed in the 
vegetation of Aden. For comparison's sake we shall add the curves 
of the Bombay Presidency and Germany. 
It is a well known fact that, looked at from a distance white, yellow, 
and red stand out best from the green of the foliage, blue and violet 
only a little, brown scarcely at all. As white, yellow, and red are 
particularly attractive to insects, and as these colours are prevalent in 
Aden, we are justified in concluding that the insects play an important 
part in the pollination of Aden plants. To what extent the statement 
is correct can only be learned by observations. 
1 Boehm, R. Notes biologiques sur quelques coleopteres de la faune desertique. In 
Bull. Soc. Entomol. d’ Egypte (1908), p. 57-64. 
lophura nana. 
Eremocossus proleuea. 
Ehthoropoca carpella. 
Limnas chrysippus (all forms) . 
Zesius livia. 
Teracolus Calais. 
Teracolus phisadia. 
Teracolus pleione. 
Teracolus nalimede. 
Catopsilia fiorella. 
Belenois mesentina. 
Synchloe glauconome. 
