MOSQUITO FAUNA OF PANAMA BUSCK 57 



ber. \Micn it pupates, the cast skin is carefully preserved in alcohol 

 in a small tube with this isolation number, which the adult specimen 

 also will bear. In this way only is it possible to be sure of associating 

 the adult with the correct larva. 



Family CULICID.^ 



Subfamily Culicin.f; 



Genus ANOPHELES Meigen 



ANOPHELES PSEUDOPUNCTIPENNIS Theobald 



This appears to be the commonest and most widely distributed 

 Anopheles on the Zone, at least during the season of the }ear in 

 W'hich the present observations were made. 



It was bred from larva; from the edges of a slowly running stream 

 near Gatun : from a large ill-smelling stagnant pool near Tabernilla, 

 caused by dumping dirt across a small stream ; from a small swamp 

 near Culebra ; from still pools of a clear, cold mountain brook near 

 the Culebra cut at Empire ; from the borders of a large stream near 

 Empire ; from a large open pool in a bend of the upper Chagres 

 River, and from a stagnant pool near Panama City. Adults were col- 

 lected at Las Cascadas, Culebra, Tabernilla, La Boca, and Colon. 



ANOPHELES ALBIMANUS Wiedemann 



This species was bred from stagnant pools at La Boca and near 

 Panama City. After my departure, Mr. A. H. Jennings bred it from 

 water in an old boat on Taboga Island, where we both had failed to 

 find any Anopheles six weeks before, though we carefully searched 

 for them. This is a striking example of the repeatedly observed 

 periodicity in the activity of tropical mosquitoes. 



Adults were also collected in large numbers by ]\Ir. Jennings in 

 the barracks at Gatun, and by the writer in houses at Tabernilla, 

 Pedro ^liguel, and Panama City. From its persistence in seeking 

 human habitations for the purpose of biting, it is reasonable to sup- 

 pose this species particularly concerned in the distribution of malaria. 



At one time in July during my stay the species became excessivelv 

 abundant in La Boca, breeding in a temporarily dammcd-up swamp 

 near the laborers' quarters. The subsequent increase of malaria in 

 these barracks caused considerable anxiety as well as extra work for 

 the Sanitary Inspector's office. 



