AEDES CALOPUS 837 



Lateral comb of the eighth segment of ten scales in a single row, the single 

 scale elongate with a pointed base, a long apical spinule and curred stout sub- 

 apical ones followed by several slender lateral ones. Anal segment short, wider 

 than long, almost ringed by the plate, which nearly touches ventrally, but is not 

 united ; dorsal tuft a pair of hairs on each side ; ventral brush moderate, directed 

 posteriorly ; anal gills long, wide, tracheate, the tips rounded. 



Pupa (plate 150, fig. 713). — Cephalothoraeic mass subpyriform, compressed 

 ventrally and posteriorly ; respiratory trumpets short, strongly flaring, obliquely 

 truncate. Abdomen rather stout, the hairs sparse and weak; eighth segment 

 with small sparse tuft at apical angles ; anal paddles large, with a simple apical 

 bristle. 



Under natural conditions the eggs are laid singly in small irregular groups 

 some distance above the margin of the water. The investigations of Finlay and 

 others show that unless the fertilized female obtains a meal of blood the eggs 

 do not mature but remain latent within the body. The eggs are laid in from 1 

 to 7 days after the female has fed upon blood. Usually the eggs are not all laid 

 at once but at intervals after successive blood-meals. 



The larvae live in accumulations of water in artificial receptacles. From 

 being originally a tree-hole inhabiting species, it is now wholly domesticated, 

 and its larva inhabits artificial accumulations of water either within houses 

 or in the vicinity of human habitations. Occasionally the larvae occur in holes in 

 trees, but always in proximity to habitations. Goeldi has found the larvae in 

 water held by bromeliads, presumably near houses, and by the still folded leaves 

 of banana plants. In the tropics the earthen jars in which drinking water is kept 

 within dwellings are a favorite breeding-place; the larvae have the habit of 

 keeping to the bottom, and, as these jars are never emptied, their presence is not 

 even suspected. Thus water may be poured from the small earthen bottles 

 used in hotels in the tropics, and, unless the bottle is quickly and completely 

 emptied, the larvae will remain behind. Holy-water founts in churches are a 

 favorite breeding-place. Out of doors the larvae occur in tanks, barrels, rain- 

 troughs and discarded bottles and tins. The larvae, when suspended from the 

 surface film, hang nearly perpendicular. They can remain below the surface a 

 long time. In the experience of Goeldi and Knab they prefer clear water and 

 while this is generally true Busck has upon two occasions found the larvae in 

 very foul water. According to Peryassu the larvae will develop in a mixture 

 of 40 per cent sea water with 60 per cent of fresh. He further states that the 

 larvae thrive very well in water containing food-refuse, such as cured or fresh 

 meat and farinaceous products or fats, and that they do best in muddy water 

 or such as contains an abundance of dead leaves and fragments of wood. 

 Peryassu states that the larva is predaceous and cannibalistic. We have ob- 

 served them feeding upon dead larvae but have never seen them attack living 

 ones. 



The habits of the imago are strictly diurnal. They frequent habitations and 

 the female probably only leaves the house in quest of a suitable place for 

 oviposition. Both sexes are attracted to man. The females are persistent 

 biters, although very stealthy in their attacks. They have developed the habit 

 of approaching from behind and when disturbed will retreat to a dark comer 

 and wait a while before returning to the attack. The bite is often imperceptible 

 and leaves comparatively little irritation. Unlike many other mosquitoes they 

 emit no sound when about to bite. The male likewise persecutes man and this 

 has led to the widely quoted statement of Ficalbi that it sucks blood ; however, 

 it does not pierce the skin but laps sweat from the surface and in this way causes 

 some irritation. This mosquito is most active during the warm hours of sun- 



