. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. ?476 OTHER BLOOD-SUCKING FLIES the pupa floats in a vertical position, breathing tln-ough tufts of threadhke fihiments which correspond to the breathing trumpets of mosquitoes. In the terrestrial forms the pupa retains the last larval skin hanging to its posterior end. The aquatic species of the subfamily Ceratopogoninae are peculiar in that the pupae nmst reach a dry surface before the adult will emerge. Little is known about the length of time required for the development from egg to adult, but it is
. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. ?476 OTHER BLOOD-SUCKING FLIES the pupa floats in a vertical position, breathing tln-ough tufts of threadhke fihiments which correspond to the breathing trumpets of mosquitoes. In the terrestrial forms the pupa retains the last larval skin hanging to its posterior end. The aquatic species of the subfamily Ceratopogoninae are peculiar in that the pupae nmst reach a dry surface before the adult will emerge. Little is known about the length of time required for the development from egg to adult, but it is probably comparable with that re- quired by mosquitoes — two weeks or less to a month or more, according to temperature. Annoyance. — The amount of annoyance which may be caused by midges is sometimes very great. The writer will never for- get his experiences with them in a collecting and fishing trip in the Cascade Mountains of Oregon. The midge which proved itself , a species of Culicoides (Fig. 218), was very local in dis- tribution, and always standing pools of shallow water were found in the near vicinity. The prox- imity of such pools was invariably Fia. 218. A "punky" or "no- proclaimed, towards evening, by see-um," Culicoides, whicli is ;i ^i n e j. i e scourge of fishermen and campers in ^^^^' Collection of great numbers of the Cascade Mountains of Oregon. thcSC inscctS OU all expOSed parts of the body, each one so minute as to be hardly visible, but in the aggregate sometimes giving the arm or shirt sleeve a dark gray color. Each one is presently the cause of an intensely itching spot. That the insects are attracted by animal smells is evident from the following experi- ence. The writer had shot a rabbit and was skinning it. .\1- most immediately after the animal was cut open and the smell of the warm bowels exposed to the air the writer found himself attacked by myriads of these insects, and was l)itten to such an extent as to
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmedical, bookyear1918
