182 



MEANS OF DEFENCE OF INSECTS. 



of which strikingly resemble those bees in shape, clothing, 

 and colour. Thus has the Author of nature provided that 

 they may enter these nests and deposit their eggs undiscovered. 



Did these intruders venture themselves amongst the 

 humble-bees in a less kindred form, their lives would pro- 

 bably pay the forfeit of their presumption. Mr. Sheppard 

 once found one of these larvae in the nest of Bombus 1 Raiellus, 

 but we could not ascertain what the fly was. Perhaps it 

 might be Volucella bombylans, which resembles those humble- 

 bees that have had a red anus. 2 In like manner Mr. W. S. 

 MacLeay informs us that he has discovered that the larvae 

 of those tropical Bombylii which have such a bee-like form 

 live on the larvae of the bees they so strikingly represent ; 

 and he suggests that probably the object of nature in giving 

 such an ant-like form to the singular spider described by him 

 under the name of Myrmarachne melanocephala is to deceive 

 the ants on which they prey. 3 



The brilliant colours in which many insects are arrayed 

 may decorate them with some other view than that of mere 

 ornament. They may dazzle their enemies. The radiant 

 blue of the upper surface of the wings of a giant butterfly, 

 abundant in Brazil (Morpho Menelaus), which from its size 

 would be a ready prey for any insectivorous birds, by its 

 splendour (which I am told, when the insect is flying in the 

 sunshine, is inconceivably bright) may produce an effect upon 

 the sight of such birds, that may give it no small chance of 

 escape. Latreille has a similar conjecture with respect to the 

 golden wasps (Chrysis L.). These animals lay their eggs in 

 the nests of such Hymenoptera, wasps, bee-wasps (Bembex), 

 and bees, as are redoubtable for their stings ; and therefore 

 have the utmost occasion for protection against these mur- 

 derous weapons. Amongst other defences the golden wasps 

 are adorned with the most brilliant colours, which by their 



1 Apis. * *. e. 2. K. 



2 Dr. Fleming, however (in Literis), doubts whether the reason here assigned 

 is the cause of the resemblance between the Bombus and Volucella ; he thinks if 

 a bee knows a stranger of its own species, it could not be deceived by a fly in the 

 disguise of a bee. But the fact that these insects lay their eggs in their nests, 

 and that they resemble humble-bees, seems to justify the conclusion drawn in the 

 text. They must get in often undiscovered. 



3 Ann. Nat. Hist. ii. 1 2. 



