April, '12] JENNINGS: MOSQUITO CONTROL IN TROPICS 135 



impossible to collect and breed sufficient material with which to work. 



A species closely related to Anopheles cruzi is remarkable for its 

 habit of breeding only in water held in the leaf axils of various species 

 of epiphytic bromeliads. In certain highly favorable localities the 

 larvae of this species are fairly common, though never abundant in the 

 sense in which the term is used in connection with the commoner 

 species. An exceedingly humid cHmate with heavy rainfall, fostering 

 a luxuriant growth of bromeliads, is the only condition under which I 

 have taken the species, which is yet to be recorded from within the 

 strict boundaries of the Canal Zone. My material was all collected at 

 Porto Bello on the coast, twenty miles east of Colon, and some seventy 

 miles in the interior, near the headwaters of the Pequini River, 

 both localities being within the area of heaviest rainfall of the region. 

 Like the last, this species was not observed free in the adult state, 

 even when in camp near its breeding places. Nothing is known of its 

 relation to malaria transmission. Its rarity and the infrequency of 

 conditions suitable to its propagation along the line of the canal 

 render it economically negligible. 



In the foregoing notes, the data relating to the transmission of 

 malaria by Isthmian Anopheles are quoted from the published work 

 of Dr. S. T. Darling, Chief of Laboratory, Ancon Hospital. 



The division of the Department of Sanitation charged with the 

 work of mosquito control is composed of a chief sanitary inspector and 

 his assistant, three division inspectors, and about twenty-five inspect- 

 ors apportioned among the seventeen line stations or districts. Each 

 district inspector is held responsible for the physical condition of his 

 station as it affects the breeding of mosquitoes and indirectly for the 

 '' malarial rate" or cases of malaria occurring each week as expressed 

 in terms of percentage of population. In addition, he is charged with 

 the enforcement of the sanitary regulations in his station, a matter 

 of no small importance and even of difficulty in the case of the native 

 towns. In the latter duties he is supported by the police of the Canal 

 Zone, when such support is necessary. Co-operation with the local 

 district physician in all health matters is enjoined and daily reports 

 of malaria cases recorded at the dispensaries are sought for and 

 obtained. Frequent inspections of the entire station are made by 

 inspector or his assistants, these inspections including the most minute 

 detail of all physical features to the end that breeding may be 

 anticipated, or, if already established, be noted and remedied at the 

 earliest moment. 



The regular program of oiling is laid out by him and executed by the 

 foremen of oilers under his general supervision and inspection, as is the 

 work performed by other departments for the Department of Sanita- 



