88 MISC. PUBLICATION 631, IT. S. DEPT. OF AGRICULTURE 



rado, Arizona, Washington, Oregon, California. Palaearctic Region : "Northern 

 Europe" (Enderlein) . 



Biology and Pathogenesis. — The larvae normally breed in car- 

 rion. As many as 25 to 50 eggs may be deposited at a time, although 

 the number is usually smaller. In the warmer parts of its range the 

 adults appear in early spring and late autumn ; they may enter houses 

 in considerable numbers at such times. They are attracted to carrion 

 in an advanced stage of decomposition. 



A number of cases of wound myiasis in man and other warm- 

 blooded animals have been reported, out the role of this fly seems to be 

 that of a secondary invader in old and pustular lesions and conse- 

 quently of little importance in destroying tissue. 



The Genus CALLIPHORA Robineau-Desvoidy and Related Genera 



The genus Calliphora, broadly viewed, is of world-wide distribution 

 and includes the well-known larger blowflies or bluebottle flies. In 

 the Australian Region this group is well represented, and several of 

 the species are important sheep maggots. Townsend has restricted 

 the genus to C. vomitoria and its relatives. Certain workers on the 

 Australian fauna have adopted several of his restricted groups in a 

 subgeneric sense, and. with the present tendency, these will probably 

 be considered valid genera by many students in the near future. 



The genera grouped together under this heading agree in the follow- 

 ing characters : The facial carina is vestigial or lacking ; the eyes are 

 bare (except in C. quadrimaculata) ; the mesonotum behind the suture 

 is not flattened on the disc ; the lower squama is pilose above ; the wings 

 are hyaline, without definite clouded bands or areas ; and the remigium 

 is bare above. Certain other genera, such as Cynom-yopsis, also possess 

 this combination of characters, but the key to species and restricted 

 genera will exclude them. 



Pathogenesis. — Three species of Calliphora (in the strict sense) 

 have been recorded in human myiasis. The other species treated here, 

 in the genera Adichosiops, Neopollenia, and Anastellorhina, are Aus- 

 tralian sheep maggots which have not been reported in human myiasis 

 but may conceivably become so involved. Their inclusion here is justi- 

 fiable only on this suspicion ; reference to the Australian sheep-maggot 

 literature will yield much information on their biologies. 



Literature. — The amount of taxonomic literature on this genus is 

 great ; the following will be useful : For the North American species, 

 Hall (49) ; for the Australian species, Hardy (54) ; for the adults 

 and larvae of the New Zealand species, Miller (90) ; and for the larvae 

 of the Australian species, Fuller (41, p. 78) . A large amount of litera- 

 ture on the Australian sheep-maggot problem is available; an im- 

 portant bulletin on this subject is the report of the Joint Blowfly Com- 

 mittee (Tillyard and Seddon, 148). 



Life Histories. — Normally the blowflies, such as those belonging to 

 Oynomyopsis and related genera, are scavengers feeding on decaying 

 animal matter; sometimes they invade the diseased tissue of wounds 

 or adjacent healthy tissue, and rarely other breeding media are chosen. 

 The adult flies may be attracted to flowers, feces, overripe fruits and 

 other decaying vegetable matter, fresh or tainted meat, and sores of 

 living animals. The females are oviparous. Development is usually 

 rapid, the third larval stage often being attained on the second or third 

 day after hatching. 



