CONTROL OF MARSH MOSQUITOES 391 
Referring again to the breeding of mosquitoes in catch-basins or sewer-traps, 
it was shown as early as 1900 by Mr. T. Pergande, of the Bureau of Entomology, 
that the common rainwater-barrel mosquito breeds in small sewer-traps in the 
rear of houses in southeast Washington. He determined this point by putting 
a gauze screen over the sewer-trap in his own yard and finding adult mosquitoes 
under the screen, morning after morning. Of late years, in practically all the 
city of Washington, and in fact, notably in the northwest section, where is to 
be found the better class of residences, and where the general conditions are such 
as to preclude the possibility of the breeding of mosquitoes in other places, sewer- 
trap bred mosquitoes are very annoying, especially during the dry spells in 
July, August and September. At one time the city catch-basins, located at 
the corners of the streets, were flushed at least once in ten days, under the orders 
of an efficient official in charge of sewers for the District of Columbia. This 
procedure, if fully carried out, would prevent the breeding of mosquitoes in 
these basins. The private catch basins, usually situated near the kitchen door, 
are not under city control and are so constructed as to hold water indefinitely 
and to permit the breeding of a lesser number of mosquitoes during a protracted 
dry spell. It is easy to avoid this breeding by putting a small cupful of kero- 
sene into the sewer trap at intervals of from ten days to two weeks. But the 
difficulty arises that during the months in question, in the northwest quarter 
of the city, many houses are closed for the summer, and the treatment of the 
catch-basins on the premises of temporary absentees can only be accomplished 
by someone in authority, as a sanitary inspector, for example. Malarial mos- 
quitoes occasionally breed in these catch basins, as one of us (Dyar) found two 
larvee of Anopheles in a small catch basin in the yard of his premises during 
August, 1912. They were easily removed by flushing the drain. 
REMOVAL OF BROMELIACEOUS PLANTS. 
Sir Rubert Boyce, in his “ Mosquito or Man?,” calls especial attention to 
the wild pines or Bromeliacex as breeding places of mosquitoes in the American 
tropics, and to the extraordinary numbers in which these epiphytes occur in 
certain localities. He states that one Saman tree, which was cleaned up for the 
purpose of destroying mosquito breeding-places, yielded 26 ceart-loads of these 
epiphytes whose total weight was 3.62 tons. He shows that each plant may hold 
from ten to twenty ounces of water and that the total volume of water repre- 
sented by these parasites of a single tree was probably equivalent to a good-sized 
pond. 
DRAINAGE MEASURES AGAINST NON-DOMESTIC SPECIES. 
The drainage of swamp areas for agricultural or other industrial reasons 
needs no argument nor treatment here. The value of reclaimed swamp land for 
various purposes is treated somewhat in extenso in an earlier section, “ Value 
of Reclaimed Lands.” The drainage of swamp areas primarily in order to im- 
prove sanitary conditions and to reduce the annoying scourge of mosquitoes, 
which in itself frequently prevents the proper development of neighboring 
