IB5 



they hang down from the cobwebs; every cobweb often carries about thirty to forty 

 specimens; where it lias been possible to count the number I have often found 

 about SO to 100 upon a square meter. 



Even in summer when the Anophelines are mainly to be found in the stables 

 the cattle is often in the fields; on the larger farms they are mainly out of doors 

 day and night, on the smaller ones the cattle is driven into the stable before night. 

 In the last case the number of Anophelines is exceedingly large. In every stable 

 there are however almost always a few pens in which young cattle or sick ani- 

 mals have been locked in. It is then very peculiar to see that even that part of 

 the ceiling and walls which borders on these pens contains a much larger num- 

 ber of mosquitoes than the empty pens. To get a true estimate with regard to the 

 number of Anophelines a very careful examination is necessary; it has been shown 

 that a great many mosquitoes hide themselves between the collar-beams and the 

 ceiling and similar localities which are almost excluded from examination. — It 

 can also be shown that where among a series of stalls, each with its head of cattle, 

 there are some empty ones, the number of Anophelines over these empty stalls is 

 smaller than over those which contain cattle; nor is the ceiling over the middle 

 walk so closely covered as the ceiling over the stalls. 



4. Even in those farms where the stables contain large numbers of mosqui- 

 toes, the rooms occupied by the family are almost quite free from mosquitoes. 

 The opposite may be the case and more especially this has been the case upon 

 some large estates where all the cattle has been out in the meadows for a long 

 time, and the servants' rooms have been in connection with or very near the stables. 



- As a common rule it may however be pointed out that on most of our farms 

 there is the most striking contrast between the number of mosquitoes in stables 

 and in the living rooms. 



Accounts from excellent observers, in whom I have the greatest confidence, seem 

 to point to the fact that in localities where there are exceptionally many breeding 

 places for Anopheline-larva?, and where the number of cattle present in the vicinity 

 is but slight f. i. in the little town of Silkeborg (about 10.000 inhabitants), quite 

 surrounded by lakes and moors, it seems as if the mosquitoes here may enter 

 the houses; this may especially be the case in autumn. Personally I have not myself 

 had any occasion to corroborate this assertion. 



5. The mosquitoes of the stables are almost all blood-filled: extremely thick; 

 where I have tried to count I have always found that about 00 " o have the sto- 

 machs full of blood and only 10 °/o have empty stomachs; in many of them the 

 contents of the alimentary canal is black, in many of them it is red. Rather often 

 we find specimens where the hind part of the contents is black, the fore part is 

 red. In my hatching cages I have seen that an A. maculipennis with red contents 

 of the alimentary canal in the course of twenty-four hours has altered it to black. 

 When therefore I find mosquitoes with contents half black and half red, I am in- 



