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cisterns, etc., near or in houses. Many generations occur in a year, 

 and most of them are domestic in their habitat with the exception of 

 a few of the late summer ones. Theobaldia (Culex) annulata has a 

 similar Ufe-history, but is more rarely met with. 



Ochlerotatus {Culex) nemorosus is the commonest mosquito in 

 Denmark. The larvae are found in the spring in small puddles in 

 beech forests, which become quite dry in the summer. The adult 

 appears in May, and is the common forest mosquito at the beginning 

 of the summer. It does not suck blood until 8 days after emergence. 

 The eggs are deposited in the dry forest ground, and hibernation 

 occurs in this stage. It has only one generation a year. 0. (C.) 

 ornatus appears in the spring in company with 0. nemorosus. The 

 larvae are found from October to November in forests in small pools, 

 often the same as those in which larvae of 0. nemorosus occur in spring. 

 Hibernation takes place as a larva, but the winter is a critical time 

 and many individuals perish during it. It is undoubtedly a southern 

 species, which is better able to survive the winter in warmer climates. 

 0. {Culex) nigrifes, a species common in all arctic countries, must in 

 Denmark be considered to be a rehc of the ice age. Its larva is found 

 in October to November in small shallow puddles in spruce forests. 

 The adult appears in December at a temperature of about freezing 

 point, and it passes the rest of the winter hiding in moss, undergrowth, 

 etc. Pairing probably takes place in mid- winter. The larvae of 

 Ochlerotatus geniculatus {Culex lateralis) Uve in small collections 

 of stagnant water in holes in trees, especially at the base of old beeches 

 and oaks, and are found from mid-July to the beginning of September. 

 Hibernation must take place elsewhere and in another stage, but the 

 details are unknown. The newly- hatched larvae of 0. {Culex) cantans 

 are found in May in small puddles in forests together with the older and 

 therefore larger ones of 0. nemorosus, and the imago appears two or 

 three weeks after the latter species. It does not suck blood until a 

 fortnight after emergence. Together with Ochlerotatus (C.) vexans 

 this is the common late summer mosquito in the forests. The eggs 

 are laid in the autunm and hibernate. 



The larvae of OcJderotatus {Culex) annulipes are found in ponds filled 

 with vegetation on the edges of forests or in meadows in the spring 

 (May). The adult appears at the end of May. As these ponds dry 

 up in the summer, the eggs must be laid on dry land in the 

 autumn and hibernate. The larvae of 0. annulipes and 0. cantans 

 are only separable by their colour, which perhaps is due to 

 their habitat in shaded forest ponds or exposed meadow ones. 

 In Ochlerotatus {Culex) vexans, the larva is found in the spring in 

 flooded meadows. The adult appears in May, and as meadows \\\\\ 

 dry up in that month, oviposition, which must be supposed to 

 take place in June, must be effected on dry land. The egg-stage is 

 thus very long, lasting through the summer and ^^inter. In certain 

 locaUties this species is very abundant and especially troublesome to 

 horses. The habits of Ochlerotatus {Culex) dorsalis (a species common 

 in Copenhagen) and Theobaldia (C.) morsitans have not been studied by 

 the author. 



Aedes cinereus is found in very large numbers in damp meadows 

 and marshes. It always remains near the ground and therefore does 

 not bite higher than the knees. Hibernation, according to German 



