1902] MICROSCOPICAL JOURNAL. ) 53 
4 
Professor Howard on Mosquitoes. 
Mosquitoes: how they live; how they carry disease ; how they are 
classified; how they may be destroyed. By L. O. Howard, Ph. D., 
Department of Agriculture. 241 pp. 50 figures. $1.50, McClure, Phil- 
lips & Co. New York. 
Incidentally he tells how to collect and preserve these 
small scavingers. The adults are very fragile. The scales 
easily rub off from their bodies and legs. The antennae 
break. As these parts are used in identification of the 
50 or more species on record they are not handled with 
the fingers, They are caught by placing an inverted vial 
over them while at rest. Then plug with absorbent cot- 
ton saturated with chloroform. 
With a tin. achromatic triplet lens, all the specific 
characters can be made out including the teeth of the tar- 
sal claws if one is skilled. Otherwise, one may break off 
the tarsus and mount it upon a slide in glycerine or Can- 
ada balsam for examination under higher power. Howard 
says: ‘‘Itis not advisable to mount adult mosquitoes bodily 
on slides in any medium whatever. They should not be 
preserved in alcohol or formalin but should be kept dry 
in vials.” They are to be moved or mailed in pill boxes 
padded with cotton. Dr. Howard, being an entomolo- 
gist, arranges his specimens for museum purposes by the 
triangular tag method, which he describes fully. 
Dr. Howard considers the relation of malaria to mos- 
quitoes. He regards malaria forms as protozoan (animal), 
not bacterial (plant-life). These protozoa go through a 
stage in the human red blood-corpuscles, feeding upon 
the red pigment and producing spores which later are 
liberated and this marks the beginning of malarial pros- 
tration. Another stage must occur anywhere outside of 
the human body and the stomach of mosquitoes (certain 
ones at least) offers the necessary habitat. Here appear 
the zygotes and centromeres and what under very high 
powers are shown to be spindle-shaped cells, known as 
