OF \VASHJ.\CTO\. VOLUME XIV, 1012. 109 



interest. While a number of species of Leptidse of other 

 genera have been reported as blood-suckers, these records 

 are so few and scattered, and some of them of such a question- 

 able character, that it seems worth while to bring them together 

 and review our present knowledge of the blood-sucking habit 

 in the Leptidse. 



In Europe Leptis scolopacea and L. strio-osa have been 

 reported as attacking man. In North America we have the 

 record of Osten Sacken, who observed the habit in an un- 

 determined species of Symphoromyia at Webber Lake, Cali- 

 fornia, and made the statement that the female stings pain- 

 fully and draws blood. 1 For South America we have the sin- 

 gle record by Philippi of the habit in Dasyomma obscurus 

 from Chili. "Frequens in prov. Valdivia, mensibus Decembri 

 et Januario, avide sanguinem rostro petit." 2 



Thus it w r ill be seen that our information concerning blood- 

 sucking Leptida? is extremely meager, and confined, at least 

 for the most part, to single records for each species. Further- 

 more, the European records may be confidently eliminated, as 

 they are undoubtedly erroneous. They have been discussed by 

 the late G. H. Verrall, an exceedingly careful worker, as follows : 



I cannot accept the records of the bites of Leptis scolopacea and L. 

 strigosa as recorded by MM. Heim and Leprevost in Bull. Soc.Ent. France, 

 LXI, and civ. (1892); to begin with, neither gentleman is well known in 

 Dipterology, and in each case only one specimen was observed; M. Heim's 

 specimen was first recorded as L. scolopacea but subsequently altered to 

 L. strigosa, while M. Leprevost did not attempt to name his specimen but 

 stated that it was named by M. Gazagnaire, whose name again is not 

 known in Dipterology; I cannot help thinking that the aggressive appear- 

 ance of Leptis led these gentlemen to believe that a species of that genus 

 caused the bites which had been really given ]yy ffcematopota,a& the bites of 

 the latter cause in me the exact symptoms detailed;! would further remark 

 that the status of L. strigosa is eminently uncertain and that it would 

 require a very first-rate Dipterologist to identify that species or variety. 3 



Verrall \s criticism is supported by the structure of the 

 mouthparts of Leptis. Becher studied the mouthparts of 

 several Leptidie and his investigations show that both sexes of 

 Leptis and Chrysopila agree in structure with the male of 

 C/irysops (Tabanida 1 ) and lack the mandibles. 4 



On the other hand, Becher shows that the females of 

 Atherix and Symphoromyia have fully developed mandibles, 

 like the female Tabanida-. 



Regarding our American records, then, the structure of 

 the mouthparts supports the observations in the case of 



'Bull. U. S. Geol. Survey, III, p. 224, 1877. 



-'Aufzahl. d. chilen. Dipteren, Verh. zool. bot. Ges. Wien, xv, 725, 1865. 

 3 British Flies, vol. 5, p. 235, 1909. 



4 Denkschr. kais. Akad. Wiss. (Wien), Math.-Naturw. Classe, vol. 45, p. 

 143-144, 1882. 



