244 Annals Entomological Society of America [Vol. VIII, 
other stations. Adults of farsimaculata have been picked 
up in passenger and freight cars forty miles from Gatun, and 
later in the season larvae were found at Balboa and Ancon 
which upon maturity yielded tarsimaculata. There is no doubt 
whatever in the writer’s mind as to the origin of this new 
breeding area; the invaders in these swamps of Ancon and 
Balboa came from the Gatun influx. The writer examined at 
regular intervals the mosquito catch from Monte Lirio and 
Frijolles, seven and thirteen miles distant from Gatun, and at 
first the Anopheles were wholly albimanus and malefactor, 
but toward the end of February, tarsimaculata was not at all 
uncommon. 
To outline briefly the history of the breeding at Gatun, it 
was generally supposed by several inspectors that the trouble 
came from the floating islands and vegetation in Gatun lake. 
An inspection from a launch revealed nothing. Mr. J. A: 
Corrigan, the inspector in charge had a totally different idea, 
and after the others returned without results, he invited them 
to the actual source of trouble, the salt-marsh north-west of 
Gatun. How he came to that conclusion is probably explained 
on the basis that he knew not merely his district, but also the 
territory just outside of it. At any rate, once well within the 
thickets 1n this marsh, all agreed it was as near true to the 
most authentic descriptions of Hades as could be had. 
Nor was this tormenting scourge confined to the marsh. 
The early part of January, the clerks in the Administration 
building at Gatun began to place blotters on the seats of their 
wicker chairs; some claimed this measure only alleviated the 
discomforts. Colonel Phillips came to investigate, and left 
the place with an Anopheles clinging to his coat, and this. 
mosquito held on notwithstanding that a ten-mile wind flapped 
violently the coat. The writer noted on March 20th, a. m., 
a negro with a female tarsimaculata resting on his coat, and. 
traced it over two hundred yards. Ina previous paper (1913) 
the writer reported having carried A. albimanus into Corozal 
which had been clinging to his clothes for quite a distance. 
Anopheles cling more tenaciously to clothing than do Culex. 
At the hotel, particularly at night, mosquitos insisted in 
painfully assisting the men trying to eat. The location of the 
door, as well as the fact that it was practically continuously 
open during the hours when mosquito activity commenced, 
