THE FLIES THAT CAUSE MYIASIS IN MAN 157 



This species has been reported to produce intestinal myiasis, but 

 such a possibility seems highly questionable. Inasmuch as this species 

 occurs in fruits which are still fit for human consumption, it is al- 

 most certain that larvae may be swallowed from time to time. Causey 

 (26) experimentally fed larvae to a puppy, and obtained no survival 

 of the larvae. Records of this species in intestinal myasis may be due 

 to misidentification, misinterpretation, or subsequent contamination. 



DROSOPHILA FUNEBRIS (Fabricius) 



Recognition Characters. — Adult : The facial carina is prominent ; the great- 

 est width of the cheek is about one-fourth that of the eye. The mesonotum and 

 scutellum are reddish brown and unmarked, the pleura likewise unmarked but 

 becoming somewhat paler below. The acrostical hairs are in eight rows. The 

 front basitarsus of the male is simple. Length about 2.5 mm. Larvae (fig. 93, B) : 

 The larvae of this species are somewhat larger than those of D. melanogaster, 

 and measure about 7 mm. in length. The posterior end tapers to the spiracles, 

 which are black ; the spinous areas completely encircle the anterior portion 

 of each segment, though they are more pronounced ventrally ; tfte last segment and 

 the bases of the spiracles are covered with fine hairs. 



Geographical Distribution. — Nearctic Region: Quebec, Ontario, Alberta, 

 British Columbia, Maine, New Hampshire. Vermont, Massachusetts, Rhode 

 Island, Connecticut, New York, New Jersey, Pennsylvania, Maryland, District of 

 Columbia, Virginia, Georgia, Alabama, Mississippi, Tennessee, Ohio, Michigan, 

 Indiana, Illinois, Kentucky, Minnesota, Wisconsin, Iowa, Missouri, South Da- 

 kota, Nebraska, Kansas, Arkansas, Louisiana, Oklahoma, Texas, Idaho, Wyom- 

 ing, Colorado, Utah, Nevada, New Mexico, Arizona, Washington, Oregon, Cali- 

 fornia. Neotropical Region : Mexico, Costa Rica, Panama, Puerto Rico, Trinidad. 

 Palaearctic Region : England, Spain, France, Netherlands, Italy, Sicily, Norway, 

 Sweden, Finland, Denmark, Germany, Austria, Hungary, Rumania, Azores, 

 Canary Islands, European Russia, Kamchatka, China (Soochow), Japan. Ethio- 

 pian Region: Rhodesia, South Africa, Mauritius. Australian Region: Western 

 Australia, New South Wales. 



Biology and Pathogenesis. — This species will breed on various 

 kinds of fruits, though it is not so often found on fruits as are many 

 other species. It will breed freely in animal matter that has been 

 preserved in formalin and then allowed to dry ; it has been reported 

 from formalin vats, fleshy fungi, cesspools, and human excrement. 

 Oviposition begins when the females are about 3 days old ; at moderate 

 summer temperatures the eggs will give rise to adults in about 2 weeks. 



This species has been recorded as producing intestinal myiasis in a 

 man in Virginia. The breeding habits of the fly and its endurance of 

 so powerful a chemical agent as formalin would make this record seem 

 more plausible than records for D. melanogaster. Perhaps records 

 for D. melanogaster may really be due to misidentifications of D. 

 funebris. 



The Family TYLIDAE 



TREPIDARIA CIBARIA (Linnaeus) 



Synonym. — Calobata cibaria (Linnaeus). 



Pathogenesis. — This species has been reported in connection with 

 intestinal myiasis in man, but the record is highly questionable. Lit- 

 tle is known of the biology of the flies of this family. Some breed in 

 excrement, including that of man, and it is probable that the record 

 was obtained through the examination of a contaminated stool. 



