THE FLIES THAT CAUSE MYIASIS IX MAX 153 



necticut, New York, New Jersey. Maryland, District of Columbia, Virginia, 



North Carolina. Florida, Ohio, Michigan. Indiana. Illinois, Minnesota, Wis- 

 consin. Missouri, Nebraska, Kansas. Idaho. Utah. 



Biology and Pathogenesis. — This species has been reported by 

 Riley (120) as involved in gastrointestinal myiasis (not auricular, as 

 stated by Metcalf). 



TUBIFERA ARBUSTORUM (Linnaeus) 



Synonym. — Eristalis arbustorum i Linnaeus t. 



Recognition Characters. — Adult: This is a blackish fly, with short hair: 

 the mesonotum is uniformly colored: the abdomen has the apices of the second 

 to fourth segments narrowly yellow, with prominent yellow spots on the sides 

 of the second and sometimes the third segment. The face is entirely whitish 

 pollinose; the pubescence near the base of the arista is several times as long 

 as the greatest diameter of the arista : the middle tarsi are reddish at the 

 base; and the third abdominal segment has a broad snbbasal as well as a 

 broad subapical opaque band. Length about 11 mm. Larva: Xo satisfactory 

 distinguishing characters can be given at present. 



Geographical Distribution. — Nearetic Region: Labrador. Nova Scotia, New 

 Brunswick. Quebec, Ontario. Maine. Xew Hampshire. Vermont. Massachusetts. 

 Rhode Island. Connecticut, Xew York. Xew Jersey. Pennsylvania. Maryland. 

 District of Columbia, Virginia, North Carolina, South Carolina. Ohio, Michigan. 

 Indiana, Wisconsin. Missouri. Wyoming. Utah. Washington. Neotropical 

 Region: Jamaica. Palaearctic Region: Faeroes, Ireland. Scotland. England. 

 Spain. France. Xetherlands. Switzerland. Italy. Corsica. Sardinia, Sicily, Nor- 

 way, Sweden. Finland. Lapland (Swedish), Denmark. Germany, Czechoslovakia. 

 Austria. Hungary. Rumania. Gret-co. Azores, Morocco. North Africa. Syria. Iran, 

 Siberia (Tobolsk I . Manchuria. Oriental Region : India (Kashmir). 



Biology and Pathogenesis. — Adults have been reared from larvae 

 said to be passed with the feces by a patient in Germany. 



The Genus HELOPHILLS Meigen 



Considerable confusion has arisen in regard to the true name for 

 this genus. Some writers h*ve used Tubifi /•'/. but that name is 

 properly applied to quite another genu-. 



The adults are medium-sized, blackish but brightly marked rlies. 

 with prominent longitudinal vittae of yellowish pollen on the thorax 

 and prominent yellow tegument ary side spots and bands on the 

 abdomen. The eyes are bare: the antennae are much shorter than 

 the face, with an oval third segment and a dorsal arista; the face is 

 marked with a median shining stripe. The hind femora are thick- 

 ened, but without a tooth or tubercle. The thoracic squamae are 

 hairy above: the marginal cell is open; vein r^ 5 curves strongly 

 into the middle of the apical cell. 



Larvae. — The larvae are similar to those of Tubifi ra. However. 

 the tracheal tubes, which are straight in Tubifera, are undulating in 

 this genus (tig. 90. D ) : the integument is sufficiently transparent that 

 these structures can be seen without dissection. 



HELOPHILUS PENDULUS (Linnaeus) 



Recognition Characters. — Adult : The antennae and the polished facial stripe 

 are black. The pollinose stripes of the mesonotum are yellowish and reach 

 the scotellum. The femora are black with broad yellow apices. The second 

 and third abdominal segments each bear a pair of prominent yellow tegunietitary 

 spots, which do not reach the posterior margins of the segments except narrowly ; 

 the fourth segment bears an interrupted pollinose cross band: the narrow poster- 

 ior margins of the second and third, and fourth segments are yellow in ground 



