188 REMARKABLE INSECTS. 



branches, and there keep up a constant distillation of a clear 

 fluid, which, dropping to the ground, forms a little puddle 

 below. If a vessel is placed under them in the evening, it con- 

 tains three or four pints of fluid in the morning. The natives 

 say that, if a drop falls into the eyes, it causes inflammation of 

 these organs. To the question, whence is this fluid derived, the 

 people reply that the insects suck it out of the tree, and our own 

 naturalists give the same answer. I have never seen an orifice, 

 and it is scarcely possible that the tree can yield so much. A 

 similar but much smaller homopterous insect, of the family 

 Cercopidce, is known in England as the frog-hopper (Aphrophora 

 spumaria), when full grown and furnished with wings, but 

 while still in the pupa state it is called ' Cuckoo-spit,' from the 

 mass of froth in which it envelops itself. The circulation of 

 sap in plants in our climate, especially of the graminacese, is not 

 quick enough to yield much moisture. The African species is 

 five or six times the size of the English. In the case of 

 branches of the fig tree, the point the insects congregate on is 

 soon marked by a number of incipient roots, such as are thrown 

 out when a cutting is inserted in the ground for the purpose of 

 starting another tree. I believe that both the English and 

 African insects belong to the same family, and differ only in 

 size, and that the chief part of the moisture is derived from the 

 atmosphere. I leave it for naturalists to explain how these 

 little creatures distil both by night and day as much water as 

 they please, and are more independent than her majesty's steam- 

 ships, witli their apparatus for condensing steam ; for, without 

 coal, their abundant supplies of sea-water are of no avail. I 

 tried the following experiment : Finding a colony of these in- 

 sects busily distilling on a branch of the Ricinus communis, or 

 castor-oil plant, I denuded about 20 inches of the bark on the 

 tree side of the insects, and scraped away the inner bark, so as 

 to destroy all the ascending vessels. I also cut a hole in the 

 side of the branch, reaching to the middle, and then cut out the 

 pith and internal vessels. The distillation was then going on 

 at the rate of one drop each 67 seconds, or about 2 ounces 5|- 

 drachms in 24 hours. Next morning the distillation, so far 

 from being affected by the attempt to stop the supplies, suppos- 

 ing they had come up through the branch from the tree, was 



