THE INSECTS. 121 



of the orange family and the Aristolochias. This 

 last genus has a very acrid secretion and its flowers 

 are sometimes quite offensive to the smell. The 

 cousins of the European cabbage butterfly cannot 

 find plants of the same family here, so they feed 

 upon the nearly allied Capparidacese ; we have, 

 however, raised Pontia monuste from a box of 

 mustard plants. It seems as if the fact that 

 Cleome and mustard are related was recognised 

 by the butterfly. 



The bean family (Leguminosse) is well repre- 

 sented, and quite a large number of butterflies and 

 moths feed upon the different species. One of our 

 most interesting butterflies is the yellow Callidryas 

 eubule, which feeds on several species of Cassia. 

 It has been noted since the time of Columbus for 

 its habit of migrating in great numbers. The 

 discoverer of the West Indies saw a great flock off 

 Cuba which was dispersed by a storm, and since 

 his time they have been seen from the Caribbean 

 Sea down to Patagonia. Where they come from 

 is as much a mystery as their destination. We have 

 seen them crossing the Demerara River for hours in 

 a steady even flight. At a distance the appearance 

 of a yellow line was produced, but near at hand they 

 were seen to be a yard or two apart. Schomburgk 

 timed a flight as lasting eight hours, extending up 



