Tineidae 
annually a sum of money which is enough in amount at the 
present time to pay the interest upon the national debt. 
Genus ADELA Latreille 
The moths of this genus are remarkable for the enormous 
length of their antennae in proportion to their size. We have 
represented one of the commoner species on Plate XLVIII, Fig. 
45. It received the specific name bella at the hands of the late 
Mr. V. T. Chambers. The base of the antennae is black, and the 
extremity is white. This fact has prevented the photographer 
from getting a full representation of the length of the organ in our 
cut. This is much to be regretted, and the student must add in 
his imagination to the antennae, as they are shown, a thread-like 
extension, extending fully three eighths of an inch beyond the 
apparent ending of the organs as depicted. The moths may be 
found in shaded woods in June feeding upon the flowers of 
Asclepias. 
Genus PRODOXUS Riley 
The relation of the insect world to the life of plants has been 
the subject of a great deal of interesting inquiry in recent years. 
It has been discovered that many genera and species depend for 
their fructification and consequently for their continued preserva¬ 
tion upon the agency of insects. Without the kind attention 
which they receive from the tiny creatures of the air, they would 
not produce seed, and the race would speedily -become extinct. 
One of the most beautiful illustrations of the interdependence of 
the world of plants and the world of insects has been discovered 
in the case of the Tiheid genus Pronuba. This insect has be¬ 
come specialized to a remarkable degree, as we shall have occa¬ 
sion to show in speaking of it. In fact, without its agency the 
pollenation of the plants belonging to the genus Yucca is never 
accomplished. But, curiously enough, associated with it and 
closely resembling it superficially is a genus of moths which does 
not possess the power of pollenizing the Yucca, but which is 
represented by many species the larvae of which feed in the stems 
of the various species of Yucca. The Yucca plants depend for 
the perpetuation of the species upon the moth Pronuba. The 
moth Prodoxus depends upon the Yucca plants for life, and thus 
437 
