Vol. XXlii] ENTOMOLOGICAL NEWS 2OI 



irregular stripe across the mesepimeron ; from this stage this stripe 

 grows in width posteriorly till it occupies nearly the entire area (pat- 

 tern II, as described under moesta) ; this stage represents the maximum 

 development of black on the thorax and is attained by only a single 

 specimen. 



Abdomen black above, pale below on the sides on all segments but 

 7, pale narrow blue basal rings on 3-7, a longitudinal middorsal stripe, 

 absent or very reduced on 6-7; 9 and 10 variable, generally gray or light 

 brown, excepting the lower lateral margins and ventrally, and a black 

 lateral spot on either side, near the middle, of 9; this spot on 9 may be 

 wanting or it may be developed into an elongated spot. 



Abdominal appendages similar to moesta (see Fig. 29, Tab. 4, 

 Biol. Centr. Am. Neur.), but the inferiors are longer than the superiors 

 (not equal), and are terminated by a large, rounded, pale tubercle. 



Female. Similar to the male. Black area on rear of head reduced 

 to a spot on either side. 



Darkest thoracic pattern : A black line on either side of the mid- 

 dorsal thoracic carina, originating just below the antealar sinus and 

 reaching the mesostigmal lamina, separated from the black middorsal 

 carina by pale area equal to the width of the black line, the dark line 

 and the pale area next the carina together occupy less than one-half 

 the area of the mesepisternum. This black area is developed in a pale 

 area which is present on the mesepisternum as well as on the mese- 

 pimeron and metepimeron, as described for moesta. In other speci- 

 mens the black dorsal lines on either side of the middorsal carina 

 are reduced and in three specimens they are wanting altogether. No 

 such lines are present in moesta. All specimens show more or less 

 distinctly the pale areas above mentioned as present on females of 

 moesta. 



Abdomen darker than in any moesta examined, though, if the red- 

 dish brown of moesta be considered dark, moesta has a more extensive 

 area dark colored, since in moesta there is no longitudinal middorsal 

 pale area, while in intruda the dorsum is black (instead of reddish 

 brown as in moesta), and there is a narrow but sharply denned and 

 distinct pale longitudinal middorsal stripe, narrowest on 7, where it is 

 reduced to the merest line. The lateral black is carried posteriorly 

 on to 9, usually to its apex ; 10 is pale colored. Sides of abdomen below 

 the black, pale colored. 



The mesostigmal lamina of intruda differs from moesta as follows: 

 in moesta the posterior (or superior) lobe of the lamina is symmetrical 

 with the border of the lamina on either side similarly curved, while 

 the anterior (or inferior) border of the lamina is distinctly concave, 

 the external angle of the lamina being correspondingly acute; in 

 intruda the posterior (or superior) border of the lamina external to 



