EUCERA. 235 



do not change into pupae until mid-spring, and speedily 

 transform into the imago, which, until fully matured, is 

 closely in every part and limb covered with a thin silky 

 pellicle, wherein it lies as in a shroud, but at its appointed 

 time, regulated by some influence of which we have no 

 cognizance, active life becomes developed, it then casts 

 off its envelope and comes forth to revel in the sun- 

 shine, in close companionship with a partner which its 

 instinct promptly teaches it to find. The largest of our 

 native Nomadce is its parasite the N. sexcincta, and 

 which seems wholly restricted to it, but which is often 

 even rare in places where the Eucera abounds. The 

 female, like those of the rest of the bees, is no time- 

 waster, but flies steadily to and fro in her occupation of 

 provisioning her nest, and the male often accompanies 

 her in these expeditions, gallantly winging about with 

 extreme velocity as if to divert his sedulous companion 

 in the fatigue of her toil, by his evolutions and his 

 music, which is very sonorous. And on a fine May day 

 it is extremely pleasant in a picturesque situation to sit 

 and watch the operations of these very active insects. 

 In their recent state, when just evolved from the nidus, 

 they are very elegant, being covered with a close silky 

 down, which labour and exposure soon abrades. It is 

 said that this bee deserts her nest when she finds the 

 stranger's egg deposited on the provender laid up in 

 store, or when she meets with the Nomada within, which 

 sometimes lays two eggs in one cell. To this she does 

 not deliver battle, as does the Anthophora to Melecta, 

 but patiently vacates the nest, leaving it to the service 

 of the parasite, which is also supposed to close it her- 

 self, having been caught with clay encrusted upon her 

 posterior legs. For the accuracy of this supposition I 



