Page:Popular Science Monthly Volume 63.djvu/467

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MOSQUITOES AND THEIR EXTERMINATION.
463

pidæ, Belostomatidæ) deserve mention." He also speaks of the 'water tiger,' the larva of the large water beetle (Dytiscus), and tells of its ability to clear Culex larvæ from pools of water.

In this connection a brief description of a newly discovered mosquito,[1] to which has been given the name Eucorethra underwoodi, should be of interest, since it has been found that their larvæ devour the wigglers of other mosquitoes, and unlike other mosquitoes, the adult female insect does not bite. As the proboscis of this insect is so formed that it can not puncture the skin, it should not perhaps be called a true mosquito, though it has been classed as one, since it belongs to the family Culicidæ.

The larvæ of this insect were found by the author on January 27. 1903, in the Maine woods in the eastern section of Penobscot County, and were discovered in a spring of water from which a crew of lumbermen

Fig. 12. Larva Eucorethra underwoodi. Dorsal View.

were getting their water supply. A few days later, other larvæ of the same species were found in a similar spring about eight miles distant, though in this case, as the spring was not in use, its surface was covered with a coating of ice an inch thick. The temperature of the water at the bottom (it was about two feet deep) was 42° F.

At first sight this larva would be taken for an Anopheles of extraordinary size, as it is of the same general shape, and when the water was cleared of ice, it lay just beneath and parallel to the surface, breathing through a short respiratory siphon, as is characteristic of the larvæ of Anopheles. In this spring a barrel had been sunk and in the fifty gallons, or thereabouts, of water which it contained there were twenty-five larvæ. They were all of about the same size—13 to 14 mm. long


  1. Under the title 'A New Mosquito' a description of this mosquito appeared in Science, August 7, New Series, Vol. XVIII., No. 449.