Empididae. 83 



1909, Beiheft, 88, and some species of Etnpis s. str. see below). The 

 species are carnivorous, feeding on other Insects; I have taken E. tessel- 

 lata with Scatophaga stercoraria L. and E. stercorea with a small Tipulid 

 as prey. Poiilton 1. c. records from England the following samples of 

 prey : E. hilineata : Bihio lactei-pemiis Zett. , Empis stercorea L. ; E. 

 grisen: Pegomyia hicolor W. ; E. femorata: Hydrotæa sp., Thereva 

 hipunctata M. and piebeja L. Mijiospila meditabunda F. ; Spilogaster 

 duplicata M..\ E.tessellata: Onesia sepulchralis L., Leptis scolopaceah., 

 a Tipulid, Bibio nigriventris Hal. and marci L., Volucella inflata F., 

 Aporomyia dubia Fall., Dryomyza anilis Fall., Tipida lunata L. and 

 paludosa M., Hylemyia sp., Dilophus febrilis L. , Mydæa sp. ; E. livida: 

 Tortrix viridana L. , Crambus hortuellus Hb., Cranibus sp., Lype 

 phæopa Steph., Borborus nigrifemoratus Macq. and equinus Fall., 

 Dicranomyia dumetorum M., Stomoxys calcitrans L., Anthomyia sp., 

 Caricea tigrina F., Sepsis cyiiipsea L., Nemopoda cylindrica F. ; E. 

 opaca: Bibio ladeipennis Zett. Hamm records (Entom, Month, Mag. 

 XLV, 1909, 160) Bibios and other Diptera for E. femorata, and How- 

 lett records (1. c. XLIII, 1907, 229) Bibio varipes M. and various Tipulids, 

 Ephemerids and Perlids as prey for E. borealis. 



The copnlation of many species of Empids is connected with 

 some interesting phenomena which are particularly mentioned by 

 Howlett (Entom. Month. Mag. XLIII, 1907, 229) and Hamm (ibid. 

 XLIV, 1908, 181 and XLV, 1909, 132 and 157). The species in 

 question are E. borealis, livida, opaca, tessellata and femorata. In 

 these species the males catch, at the time for copulation, a prey 

 which they kill but do not devour; on the contrary they carry it in 

 flight to a female to which it is presented, and then the copulation 

 takes place. With regard to the species mentioned this aet is begun 

 in the air; then the pair settles down on a plant, the male generally 

 taking hold with the front legs and holding the female with the 

 posterior legs; during the aet the female sucks eagerly at the prey; 

 when copulation is finished the female seems always to drop the 

 prey. The species of the subgenus Xanthempis seem to copalate 

 without the males bringing prey to the females, and these species do 

 not copulate in the air (Hamm 1. c. XLV, 159). 



A somewhat different case is recorded by Aldrich and Turley 

 (Amer. Naturalist, XXXIII, 1899, 809). The species observed was E. 

 poplitea Loew, or a closely allied species. Of this species the males 

 were seen flying with a relatively large „balloon" which was white 

 and is described as composed of minute bubbles. In the JDalloon a 

 small, dead fly was found e. g. Chironomids and Oscinids. The authors 

 suggest, that the balloon is produced from the anal organs. The 



G* 



