REPORT OF THE STATE ENTOMOLOGIST I905 III 



is not materially increased by the digging. This was extremely 

 well shown last summer in one locality we had frequently visited 

 in the. search of larvae. Before excavations were made mosquito 

 wrigglers were present in very small numbers and sometimes 

 absent. The recent digging changed this remarkably, and newly 

 made water-filled hollows were literally swarming with the wrig- 

 glers of both malarial and nonmalarial mosquitos. The connection 

 between excavations and malarial outbreaks has long been recog- 

 nized, and this observed partiality of mosquitos for waters in such 

 places affords some expanation of why this should be the case, 

 particularly if Italians infected with a mild type of the malady are 

 employed, since when the disease is communicated in this manner 

 it is liable to assume a virulent form in nonimmunes. 



The tropical and subtropical yellow fever mosquito has much 

 the same breeding habits as our common rain barrel or house mos- 

 quito, though the wrigglers of the two species are very different. 

 Both breed largely in rain barrels, cisterns and similar places, a 

 number of generations being produced during warm weather. The 

 salt marsh mosquito and several of its allies pass the winter as 

 eggs, only a portion hatching with successive rain storms or inun- 

 dations due to high tides. Thus series of swarms are produced 

 during warm weather. A number of fresh-water species present 

 marked differences from the above, since the eggs hatch in early 

 spring and only one generation is produced. These species are of 

 small importance, though some of their allies breed more or less 

 in early summer and may prove annoying. Another group, known 

 as midsummer mosquitos, is remarkable for its very long-tubed 

 wrigglers. This includes among others the rain barrel mosquito 

 and the little black mosquito. The latter, one of our smaller forms, 

 makes frantic attempts in mid or late summer to get indoors, work- 

 ing through the mesh of ordinary wire screen. 



Destruction of mosquitos prevents the dissemination of malaria 

 and yellow fever because they are the only carriers of these diseases. 

 More than this, mosquitos must first become infected before they 

 can convey either of these disorders ; consequently the medical man 

 has only to destroy as many mosquitos as possible and then, by 

 screening, prevent others from becoming infected by biting patients 

 and his object is attained. Yellow fever cases are occasionally 

 brought to Havana and, for that matter, to New York and cared 

 for, the only precaution taken being to keep mosquitos away from 

 patients and the results have justified the procedure. It would 



