THE ANTH0MYIID.5 : OCCURRENCE AND STRUCTURE. 169 



stomach and intestines, where they may have been introduced in in- 

 cautiously eating decaying fruit and vegetables. A list of one hundred 

 and eight instances in whicli insect forms have been discharged from 

 the human body, was published forty years ago ;* among these were 

 several of Homalomyia. A list of twenty such discharges from the 

 urethra has been collected and published by Dr. Hagen,f but 

 the reliability of the testimony upon which most of them rest is ques- 

 tioned by the author of the paper, and it is thought that not one had 

 been j^roved by indubitable evidence. 



Characteristic Features of the Anthomyiidae, 



Structurally the Authomians are closely allied to the typical species 

 of the family of Muscidm^ which embraces our common house-fly, the 

 meat-fly, the blow-fly, etc., from which family they wore separated by 

 Meigen, in 1838. An obvious difference between the two is to be 

 found in the neuration. Fig. 45 represents the neuration of the An- 

 ihomyiidm, as it occurs in the wings of the Onion-fly, Pliorhia cejxirum. 

 The veins and cells are indicated by numerals and letters, and the termi- 

 nology given below is that of Osten Sacken. The venation of the 



1' 1 



Fig. 45. — Enlarged wing of the onion-fly, Phorbia c^p kvlvv. Meig. — A A, costal vein; 

 1', auxiliary vein ; 1, 2, 3, 4, 5 and 6, first, second, third, fourth, fifth and si.\th longitu- 

 dinal veins ; 7, axillary vein; 8, middle transverse vein; 9, hinder transverse vein ; 10, 

 transverse shoulder vein ; 11, anterior basal transverse vein ; 12, posterior basal transverse 

 vein; «, a, a, first, second and third costal cells ; b, marginal cell; c, submarginal cell; 

 d, e,f, first, second and third posterior cells; g, discal cell; h, ?i, h, first (the large upper), 

 second and third basal cells ; i, anal or axillary corner of the wing ; y, alar appendage 

 (alula); k, axillary incision. (For the last (liree, see Fig. 46.) 



*0n the Insects and their Larvse occasionally found in the Human Body. By Rev. F. 

 W. Hope. Trans. Eidomolog. Soc, London, ii, 1840, p. 256. 



+0n Larvae of Insects Discharged through the Urethra. By Dr. H. A. Hagen. Proc. 

 Bost. Soc. Nat. Hist., xx, 1878, pp. 107-118. 



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