Predaceous Insects and their Prey. 375 



victims on Peiialara, these beetles were by no means 

 conspicuously common, while on the same ground the 

 grasshopper, GompTiocems sihiric'ns,y^di^ positively swarming. 

 This species is certainly attacked by other kinds of Asilids : 

 an example is in fact put on record in the table (No. 

 192). The attacks upon Lepidoptera also probably 

 indicate some preference, especially when we consider that 

 only one other Geometrid victim is recorded,* and that, 

 except Di/smacJms, no Asilid is known as the captor of a 

 Crambits. 



Eutolmus (Nos. 175, 176). — Of the two species one is 

 not with certainty to be included in this genus. The 

 records are insufficient to justify conclusions ; but there is 

 one interesting point about^'?/to/m«s aincatuswhich. deserves 

 notice. The species was very common on Montserrat, and 

 14 specimens (6 $ and 8 $ ) captured July 14-15, 1901, 

 exist in the Hope Collection : yet only a single pair of 

 the insects were observed in coitn, and the female of this 

 pair was the only individual of the species observed with 

 prey (an Anthomyid fly). The coincidence supports the 

 conclusion already arrived at, that females with prey are 

 especially sought by the males (p. 367). 



Machimus (Nos. 177-205). — At least 7 species are dis- 

 criminated by ray kind friends Col. Yerbury and Mr. 

 Verrall ; and no less than 29 examples of prey are recorded. 

 These are so numerous and striking that the results are 

 shown below in a tabular form on page 876. 



Certain preferences are very obvious in this table. The 

 choice of Acridians is clearly seen in the fact that nearly 

 half the number recorded for the whole of the Asilidx are 

 found in the first two columns. Apart from this, the best 

 known form is seen to attack beetles freely, Hymenoptera 

 and Diptera slightly, while there is a single record of a 

 butterfly and a Lygseid bug among the victims. M. seti- 

 harlus is only known to attack Diptera. The British 

 species also exhibits a strong preference for Diptera ; for 

 these contribute 5 out of the 6 records of prey. The sixth 

 record is interesting, as it affords the only example of an 

 attack on the Ccrco'pidx, as yet observed among Asilids. 



Ncoitamns (Nos. 206-216). — Of the two species with 

 prey there is, in the case of the British form, N. cyanurus, 

 evidence suggesting that Diptera are the chief element in 



* See, however, footnote on p. 356. 



