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AN INTRODUCTION TO ENTOMOLOGY 



The full-grown larva leaves the yucca pod and makes its way to 

 the ground, where it spins a dense cocoon several inches below the 



surface. The adult 

 moth has a wing-ex- 

 panse of about 2 5 mm. 

 The front wings are 

 silvery white above ; 

 the hind wings, semi- 

 transparent. 



The bogus yucca- 

 moths, Prodoxus. — 

 The moths of this ge- 

 nus are closely allied 

 to the yucca-moths, 

 but differ in the im- 

 portant particular 

 that the females lack 

 maxillary tentacles; 

 they are consequently 

 incapable of pollinat- 

 ing the yuccas as do 

 the true yucca-moths. 

 The larvae of Prodoxus 



Fig. 725. — Tegeticula alba: a, side view of head and 

 neck of female denuded ; i , load of pollen ; 2, maxil- 

 lary tentacle; 3, maxillae; 4, maxillary palpi; 5, 

 antennas; b, maxillary tentacle and palpus; c, 

 an enlarged spine ; d, maxillary palpus of male ; e, 

 scale from front wing; /, front leg; g, labial pal- 

 pus; h, i, venation of wings; j, last segment of 

 abdomen of female, with ovipositor extruded. 

 All enlarged. (From Riley.) 



feed in the flower-stem or in the flesh of the fruit. But as, in Yucca 

 filamentosa at least, the flowers drop and the flower-stem withers if 

 the flowers are not pollinated, the bogus yucca-moths are dependent 

 on the true yucca-moths for the conditions necessary for the develop- 

 ment of their larvae. The pupa state is passed in the burrow made 

 by the larva. Eleven species of Prodoxus have been described. 



Family NEPTICULID^ 



In this family, as in the preceding one, fixed hairs or acuieae are 

 distributed over the general surface of the wings. In the Nepticulidas 

 the venation of the wings is much reduced; the basal segment of 

 the antennae is enlarged and concave beneath , so as to form an eye-cap ; 

 the female is without an ovipositor; the labial palpi are short; the 

 maxillary palpi are long; and the maxillse are vestigial. 



This family includes the smallest of the Lepidoptera, some of the 

 species having a wing-expanse of scarcely 3 mm. 



Although this family presents characteristics which indicate that 

 it should be placed among the generalized Lepidoptera, the venation 

 of the wings is greatly reduced. This indicates that it represents a 

 distinct line of development which in some respects has become more 

 highly specialized than are the other families included in this division 

 of the Lepidoptera. 



The frenulum of the female consists merely of a group of small, 

 functionless bristles; but in the male the frenulum is a strong, spine- 



