420 p. W. WHITING 



mass cultures and individual matings. The number was always 

 constant, and only slight variation occurred in length and 

 divergence. 



d. Genitalia. No secondary sexual characters could be found. 

 The sexes may be readily distinguished, however, by the claspers 

 of the male, as shown in figure b, and the ovipositor of the female, 

 as shown in figure e. Occasionally a moth was found that had 

 peculiar genitalia. Examination showed that these were males 

 in which the claspers were shortened, twisted, or lacking. In- 

 ternal sexual organs were apparently normal and spermatozoa 

 were present in all. 



e. Mouth parts. The adult moths do not feed. The mouth 

 parts consist of the tongue, which is formed by the maxillae; 

 the maxillary palpi, which are small and inconspicuous; and the 

 three-jointed labial palpi, which conceal the maxillary palpi. 

 The normal condition of the mouth parts is shown in figures c 

 and /. Many variations were observed in the tongue and in 

 the labial palpi. The latter will be referred to hereafter as the 

 palpi. 



Figure a shows a condition "in which the palpi are fused in the 

 median plane. The joints of each are fused with the correspond- 

 ing joints of the other, so that there results a large flat three- 

 jointed median palpus. The tongue arises from the normal 

 position above the insertion of the palpus and appears to be 

 normal in every way. Its coil is pushed aside by the palpus. 

 Figure d shows a condition in which the palpi are asymmetrical. 

 The two terminal joints of the left are lacking. The right is 

 normal. Figure I shows a condition in which the palpi are both 

 shortened symmetrically. All sorts of variations in the palpi 

 may occur, due to loss or shortening of the joints. 



The tongue may be lacking altogether, as shown in figures j 

 and k. This variation occurred in some of the mass cultures 

 early in the work. Much variation occurs also in length. The 

 elements of the tongue, maxillae, which are normally united to 

 form a tube, may be separated to any extent. The separation 

 may occur at the tip only or from the tip any distance towards 

 the base. In some cases also the basal or middle part may be 



