ANDRENA. 209 



admits of their passing through the very constricted 

 tube which connects the abdomen with the thorax. 

 Having now escaped into the air they alight upon the 

 flowers which the bee frequents, and thence they affix 

 themselves to other bees which may visit these plants, 

 and thus perpetuate the activity of the function it is 

 their instinct to fulfil. That many may be lost there 

 can be no question ; but Nature is very prodigal of life, 

 for by life it endows life, and thus its activity is en- 

 larged to a wider circle. Although the matured Stylops 

 has preyed upon all the internal organs of the bee its 

 attack is not immediately fatal, although the life of the 

 creature may be thus considerably abridged, but it seems 

 to live sufficiently long afterwards to disseminate the 

 distribution of the Stylops. A small blackish Pediculus, 

 which Mr. Kirby called Pediculus Melitta, is found also 

 both upon the flowers the bees frequent and also upon 

 the bees themselves, especially the pubescent ones ; but 

 this insect is not limited to the genus Andrena, as I 

 shall have occasion to notice. The flower I have 

 chiefly found them upon is the Dandelion (Leontodon). 

 Their peculiar economy and connection with the bees is 

 unknown ; it may be merely an accidental and tempo- 

 rary attachment, but they even accompany them to their 

 burrows. 



Another and more curious case of attack upon the 

 young of the Andrena, is instanced in the reputed para- 

 sitism of the Coleopterous genus Mdoe. The perfect in- 

 sect is a large apterous, fleshy, heteromerous beetle, ten 

 times as big as the bee. Its vermicle, having issued from 

 the egg, has the appearance of a very small pediculus, of 

 an orange colour. They are often seen upon flowers, and, 

 like the former pediculus, attach themselves to such suit- 



