Egg without such longitudinal flanges 9 



Egg with lateral "floats" (Fig. 184). Found lying on 



water surface of ground pools and rot holes 



Anap'.iehs 



Egg without lateral floats 10 



Eggs ot mosquitoes. ( Ventral side is to the right. ) 



Fig. 185. — Psorophora subgenus Psorophora. 



Fig. 186. — Aedes vexans. 



Fig. 187. — Aedes communis. 



10. Dorsal profile (Fig. 186, 188-207) less arched than 9. 



ventral profile; eggshell without spicules. Found 



in domestic containers and on soil Aedes 



Dorsal profile (Fig. 224-231) more strongly arched 

 than ventral profile; eggshell with spiral rows of 

 stubby anteriorly directed spicules. On soil subject 

 to transient flooding Psorophora !0. 



Key to Species of AEDES (Eggs) 



This key includes only species recorded from Illinois; of 

 these, eggs are not available for abserratm and fulvm: 

 pallens, which are therefore not keyed. 1 1 



1. Reticulation of eggshell at wide part of egg dififerins^ 



dorsally and ventrally 2 12. 



Reticulation of eggshell at wide part of egg alike 



dorsally and ventrally 3 13. 



2. Cells of ventral reticulation at wide part of egg elon- 



gated transversely (Fig. 188, 208). In domestic 



containers of wood or paper aegypti 



Cells of ventral reticulation at wide part of egg not 

 elongated transversely (Fig. 189, 209). In rot 



holes in trees triseriatus ! 4. 



hendersoni 



3. Dorsal profile of egg conspicuously bent near midpoint 



(Fig. 190) . . .1 19 T'. 



Dorsal profile of egg fusiform or sausage-shaped (Fig. 

 191) 4 



4. Color shiny bronze; reticulation of shell having ap- 



pearance of longitudinal lines (Fig. 191, 210). In 

 depressions subject to proh)nged or frequent flooding 16. 



vexans 



Color usually black or gray 5 



Egg small (0.6-0.7 mm); color shiny black; shell at 

 wide part of egg with cells of reticulation appearing 

 as fine transverse wrinkles (Fig. 192, 211). In 



woodland depressions in shade of low canopy 



dupreei 



Egg larger; color variable; shell at wide part of egg 

 with cells of reticulation not appearing as transverse 

 wrinkles 6 



Egg in the form of a long cone widest at anterior end 

 (Fig. 193); color shiny black; reticulations in an- 

 terior area of shell strongly raised ( Fig. 212). In 

 woodland depressions under shade of low canopy . . . 

 cinereus 



Egg not conelike; color variable; reticulations of shell 

 absent or not as above 7 



Eggshell having cells of reticulation faint except in 

 anterior area; each cell not angular but with a lateral 

 budlike expansion on each side (Fig. 214) 8 



Eggshell having cells of reticulation angular and with- 

 out visible lateral budlike expansions 11 



Eggshell having lateral buds separated from cell and 

 situated opposite each other near center of cell; 

 most conspicuous on anterior third of shell (Fig. 

 194, 213). In woodland depressions frequently 

 flooded trivittatus 



Eggshell having lateral buds not separated from cell 

 and not opposite each other (Fig. 214) 9 



Eggshell having cells of reticulation litde longer 

 than wide (Fig. 195, 214). In depressions heavily 



polluted by industrial wastes containing sulfur 



sollicitans 



Eggshell near anterior end having cells of reticulation 

 two or more times as long as wide 10 



Eggshell having lateral buds of reticulation irregularly 

 placed along margin near cen'er of each cell; shape 

 as in Fig, 196 mitchellae 



Eggshell having lateral buds of reticulation along mar- 

 gin near each end of cell nigromaculis 



Reticulation pebbly ( Fig. 215) 12 



Reticulation lattice-like ( Fig. 216) 13 



Egg slender (Fig. 197) excrucians 



Egg wider (Fig. 198) punctor 



Eggshell having margins of cells of reticulation knife- 

 like; surface of each cell smooth, or crinkles only 

 at sides (Fig. 216) 14 



Eggshell having margins O" cells of reticulation flat- 

 tened; surface of each cell marked by subcells (Fig. 

 218) 16 



Eggshell havin<5 re'iculations in low relief; surface of 

 cells flat (Fig. 199, 216) stimulans 



Eggshell having reticulations in high relief 15 



Length of egg 0.6-0.8 mm (Fig. 200, 217). In muck 

 soil under canopy of low vegetation such as cattails 

 fitchi 



Length of egg 0.8-1.0 mm (Fig. 201). In firm soil 

 in woodlands grosfbecki 



Eggshell having subcells of reticulation with angular 

 margins (Fig. 218). From margins of woodland 

 depressions 17 



45 



