394 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



of old walls. Each little tunnel usually branches 

 out into several smaller ones. The entrances are 

 usually most accurate circles, which makes the 

 work of bees of this genus distinguishable. The 

 interior of the tunnels is beautifully smoothed. 

 The females, of some species at any rate, work at 

 their excavations by night, and devote the day 

 to collecting honey and pollen for storage in the 

 cells as well as to rest from their labours. Most 

 of the species are gregarious, but a few dwell 

 apart from their fellows. 



Bees are creatures with many enemies always 

 ready to decimate their ranks. In some 

 places the Halicti are much preyed upon 

 by a solitary wasp, Cerceris ornata, which 

 stings the bees and stores them as food 

 in its own nest ; but luckily for the Halicti 

 of our own neighbourhood this wasp does not 

 appear to occur here. Of other foes the female of 

 an Halictojihagus, one of the curious aberrant 

 Coleoptera related to Stylops, to be referred to 

 under Andrena, sometimes makes its home in 

 the abdomen of Halictus. The burrows of 

 this genus are occasionally frequented by bees of 

 the genus Nomada, to be noted later, which are 

 perhaps inquiline upon them. This may 

 probably also be said of the allied genus 

 Sphecodes, which associates largely with 

 Halictus, and of the ant Myrmosa melanoccphala. 

 A Chrysid, Hedychrum, also preys upon the larvae 

 of Halictus. Of Diptera, various species, such as 

 of the genus Phorbia, &c, haunt the nests of 

 Halicti, and their carnivorous larvae probably 

 prey upon the grubs of the bees. 



