326 Annals Entomological Society of America [Vol. IV, 



This character refers to specimens before treatment with 

 caustic potash. Only a slight study has been made of this 

 character because living specimens of three of the five species 

 studied were not available. A difference however has been 

 noted between citri Risso and longispinus Targ., in the 

 former the appendages are robust and covered with granules of 

 wax, in the latter the appendages are slender and do not 

 have granules upon them, being more linear and wire like. 

 The objection to the use of this character in the deter- 

 mination of species is the ease with which the filaments are 

 removed and the danger that the specimens consequently 

 would not be in a natural condition. Also in recently moulted 

 specimens the normal waxy covering would not be formed. 

 The length of the caudal filaments in longispinus Targ. is evi- 

 dently a good character if the specimens can be examined in a 

 normal condition. 



Anal Lobes. — The anal lobes are frequently mentioned as 

 being faintly indicated, normal or prominent. Also the presence 

 of one or more setae is occasionally used. 



The observations made upon the segmentation of specimens 

 would apply very largely to a discussion of the anal lobes. As 

 a specimen becomes older and more distended with eggs the 

 anal lobes become less prominent. Consequently in the use of 

 this character the age of the individual would have to be care- 

 fully considered. In the setae of the anal lobes there is evi- 

 dently a good character. (Tables 1-5). Upon each anal lobe 

 there are generally several setae. One of these, however, is 

 much longer and more robust than the others and is usually situ- 

 ated at the caudal extremity of the lobe. This is the seta referred 

 to in the tables and discussion. The variation in the length of 

 this seta is considerable, but the limits of variation are so great 

 that this does not lessen the value of the character. The com- 

 parison of the length of this seta to the length of the setae of the 

 anal ring is probably the most useful way of expressing the 

 character. 



Setae of the Anal Ring. — The number of setae on the anal 

 ring is a generic character and although often given in descrip- 

 tions is of no importance as a specific character. Their length 

 compared to some other part of the insect is seldom mentioned. 



However, the length of these setae is a very promising 

 specific character. The variation is considerable but not so 



