3 §4 



Phylum Arthropoda 



is concrete wall, 4' is glass sash, and 4' is beaver board. On the north 

 side the wall comprises the bottom 1.5' of its height; the center 5.5' is 

 covered with 16-mesh, iron wire gauze; while the top 4' is beaver board. 

 The east end is covered by the same kind of mosquito netting for a 

 distance of 7' from the floor; then beaver board for the top 4' of the 



MOSQUITO REARING CAGE 



Fig. 68. — North and south side elevation of mosquito rearing cage. 



wall. The ceiling is beaver board. There are opaque curtains that are 

 hung just above the glass or screen on all sides. These may be rolled 

 down from the outside, so that light intensity may be fairly accurately 

 controlled. The screen door swings outward. Inside, it is guarded by 

 three, weighted cheesecloth curtains. 



Across the west end and about 3 feet from the floor level is a perma- 

 nent shelf that is 2.5' wide. Its under surface and nether walls are 

 blackened. The opening to the space under the shelf is partially closed 

 by a concrete foundation wall which extends upward for about half of 



