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especially those of the species 0. commanis, cantans and lutescens, must throw their 

 eggs above the ground during the whole of the summer. My own insufficient ob- 

 servations tend to show that the main part of 0. communis and prodotes throw 

 their eggs from the latter part of April to the beginning of July; 0. cantans from 

 the latter part of June to the latter part of August. When driving in my carriage 

 through the large forests of Gribskov near Hillerod I have visited several hundreds 

 of temporary ponds in spring and found larvae in all; later, in summer and autumn, 

 I found the same ponds covered with brown leaves, dry and indistinguishable from 

 the surrounding ground. It is most extraordinary that the huge masses of mosqui- 

 toes which almost make the sojourn in the forest intolerable in late spring and 

 during the whole of the summer throw their eggs in the summer months, the very 

 same eggs which cannot be developed without access to the water, upon wholly 

 dry land, in all the small inconspicuous hollows covered with dry leaves, and just 

 as dry in July and August as the small hills which border the hollows. It is as if 

 the mosquitoes, by means of their maternal instincts, were able to select all the 

 localities where water will appear half a year later and which to a human eye are 

 indistinguishable from the surrounding localities where there will never be water. 



Owing to the enormous amount of larvae which appear in spring in our forest 

 ponds one would be inclined to think that it would be very easy to observe the 

 egg-laying processes over the dried up surfaces of the temporary ponds. As often 

 mentioned in the previous pages this is not the case; only with great difficulty and 

 rarely have I seen the egg-laying process of the Aedini; as far as I know no one 

 has hitherto observed it in Nature itself; that it should be confined to a special time 

 of the day is rather improbable; if so, it is most likely during the night. It is most 

 probable that the egg-laying process goes on during the whole of summer owing 

 to the remarkably long life period of these species as imagines, and that only a 

 few specimens are active at every time of the day. 



Most of our Aedini belong to the forest ponds, some to the temporary ponds 

 on open land; two live in brackish water pools, one in tree-holes. 



The second group consists of Culicella morsitans, 0. rusticus and Tceniorhyn- 

 chus Richardi. It is characterized by the fact that the species do not winter in the 

 egg but in the larva stage; the latter lasts from September till May i. e. eight to 

 nine months; the imago stage as in the foregoing group is restricted to the sum- 

 mer months; the egg stage is extremely short in this group, only lasting one or 

 two months; the imago from May June to the latter part of September. There is 

 only one generation. The eggs of T. Richardi are laid in egg-rafts; how it is with 

 regard to C. morsitans I do not know, but I should suppose that they are laid 

 singly. The egg boats of T, Richardi are most probably laid on the surface of stag- 

 nant pools among vegetation, those of C. morsitans singly over the dry bottom of 

 temporary forest pools. As far as I know neither man nor cattle or horses have 

 been subject to attacks from this group in our country; further explorations will 

 most probably show that this is not correct. 



