CHOICE OF BREEDING PLACES 221 
difficult of examination, since the plants for the most part grew upon the forest 
trees thirty feet above the ground. Those that had fallen with the trees had lost 
their water. Later, however, many plants were found in places which could be 
reached, and in the water accumulations of their leaves were found breeding a 
number of species of mosquitoes, and among these the larve of Anopheles cruzit. 
He considers the species to be a typical forest insect breeding only in such places, 
and that it is responsible for the malarial attack of a mild type from which the 
railway constructionists had suffered. The genera of Bromeliacee most com- 
monly met with are said to be Bresia, Nidularium, Billbergia, Aichmea and 
Bromelia. In the water in these plants, he found bits of vegetation and a humus 
formed from them, and living in it small crustaceans, tadpoles, larve of Culi- 
cide and Chironomide. Among the other mosquitoes inhabiting this bromelia- 
water he found Megarhinus violaceus which was feeding upon the other culicid 
larve. The relation of Anopheles cruzii to this outbreak of malaria was not 
positively established. 
On the supposition that Anopheles punctipennis is not a carrier of malaria, the 
control of malaria in certain regions of the United States, through the destruc- 
tion of the Anopheles larve or breeding-places, may be simplified if a difference 
in the character of the breeding-places of A. punctipennis and A. quadrimacu- 
latus (the only other common inland species in the more northern United 
States) can be ascertained. This consideration led Jordan and Hefferan (Joc. 
cit.) to carry out the following observations : 
“In the present instance it was found that the favorite breeding-places of A. 
maculipennis * and A. punctipennis, although close together, were of quite dif- 
ferent character, as shown by the following facts relating to the distribution in 
Western Michigan. 
“ Dipping for mosquito larve was carried out in the springs and spring-fed 
pools of the northern ravines, along the river shore, in the bayou, and in rain- 
water barrels of the village. In all of these places, with the exception of the 
bayou, Anopheles larve were found in abundance at some time during three 
consecutive summers. The distribution was more extensive in 1902, merely 
because the early part of the summer was wet, and water stood longer in the 
springs and ravines. In 1903 the early part of the summer was dry, so that by 
the middle of August two springs and the river shore only were left as breeding- 
places in the immediate vicinity of the village. In the river the larve of A. 
maculipennis * are found regularly at certain places along the north shore, 
where abundant food and quiet are ensured by the wreckage and masses of river 
weed which lie a few inches below the surface of the water. Here, with the river 
running almost due west, the larve are exposed to direct sunlight. They were 
not found along the more shaded south shore. A curious instance of choice of 
breeding-places occurred in the summer of 1904. A small stream running to 
the river had, during the spring, a course of a mile or so down the ravine, but 
by August 1 it had dried to a few pools of the following character: (a) River 
inlet, 40 feet long and 7 feet wide, shaded by willows, bottom sand and mud, 
no larve; (b) Ten feet above this inlet a pool 40 feet by 4 feet in area, some 15 
inches deep, entirely without shade or vegetation, no larve ; (c) Only three feet 
from this second pool another pool of clear water, 5 feet by 3 feet in size, and 6 
* = Anopheles quadrimaculatus of this work. 
