Abstract
The hourly collections of mosquitoes by a light trap were made at a paddy field area in Utsunomiya City during the period from June 27 to August 23, 1967. 1) A total of 18, 287 adults of the following six species were collected; Culex tritaeniorhynchus (70.9%), Anopheles sinensis (24.1%), Aedes vexans (4.7%), Culex pipiens pallens (0.1%), Anopheles sineroides (0.1%), and Culex bitaeniorhynchus. 2) The considerably different patterns of nocturnal activity were observed in the important mosquito species at different nights. After sunset and before sunrise, in general, a small number of the mosquitoes were collected.
