Abstract
During the period from May to November, 1957, the writer investigated twenty-four times on thirty stumps of bamboo (Phyllostachys bambusoides Sieb. et Zucc.) in a bamboo grove in Utsunomiya City. 1. The mosquito larvae collected were of only two species : Aedes flavopictus (85.3%) and Aedes albopictus (14.7%). 2. Ae. flavopictus always appeared dominant and reached their maximum number at the end of August. Ae. albopictus reached their maximum number in the middle and end of August. The former disappeared at the end of October, while the latter at the biginning of the same month. 3. In the bamboo stumps there were formed only three kinds of larval associations : Ae. flavopictus association (73.7%), Ae. flavopictus-Ae. albopictus association (15.8%) and Ae. alvopictus association (10.5%). 4. There was not seen the phenomenon of "habitat segregation" between Ae. flavopictus and Ae. albopictus in the bamboo stumps. 5. Compared with larval fauna of the mosquitoes in the stumps of another kind of bamboo (Mosochiku) formerly reported by the writer, in the present case the results were very poor, i. e. much smaller in number of species and individuals.
