﻿THE CITRUS MEAL^' BUG 299 



"A careful nieasurenient with a micromillimeter gives the following re- 

 sults: joints 1. 2, 3, 4, 5. r,, 7, 8; 96, 88, 96, 68, 80, 81, 44, 104." 



"The formula of Conistock's measurements with the eye 8, 3, [2,7 }, (6, 5), 

 4 omitting joint 1 ; of these by myself with the eye 8. 3, (1, 2), 5, 4, (6, 7), 

 and with the micromillimeter 8, (1, 3), 2, 6, 5, 4, 7. This, I believe, is the 

 lirst time that the true measurements of the antennal joints of Dactylopius 

 citri have been given." From all of the above it is readily seen that there 

 must be a large degree of variation in the antennal articles of different in- 

 dividuals. The mounting, and the position of the insect upon the slide, no 



Figure 116. Egg Masses of Pseudococcus citri on Lemon. 



(Pom. .Tnnni. Ent. Vol. T, No. 2, Fig. IS.) 



doubt, i)lays a very important part in these determinations. For general 

 work the eye measurements (taken by the eye through a rnicroscope) must 

 be used by the average student for ready reference. In combining all of the 

 formula? of eye measurements we may fix a more exact formula as follows : 

 iS, 3, (1, 2. 7), (5, 6), 4. The combined number of antennal articles equals 

 about one-nintli the length of the insect's body. 



Rostrum — Short, stout, and in two distinct divisions, the basal division 

 being much broader than the apical. The rostral loo]) is nearh- half as long 

 as the Ijodv. 



