FAMILIiE, {Jpis. **. c. 2. «.) 15^ 



and modes of life have been regarded as peculiar 

 to a single species^ which, in fact, are the prominent 

 features of a family, or a subdivision. This, as I 

 have just had occasion to observe, has happened to 

 those ^pes, whose acculeates are distinguished by 

 a conical and very acute abdomen : the same error 

 has taken place in the present subdivision, for all 

 those ^pes which construct centunculi, or cases 

 made of the leaves of trees, to receive their eggs^ 

 have been looked upon by Linneus, and most wri- 

 ters, as varieties of one species, which that great 

 naturalist has named ^. centuncularis, and denoted 

 it chiefly by the orange coloured hairs which cover 

 the under side of its abdomen, a character which it 

 possesses in common with a large number of spe- 

 cies in this family. A similar mode of ni.dification 

 may be, and indeed very often is, the characteristic 

 of a family or genus rather than a species : thus, 

 the cells of the different species of the Bomhina- 

 trices are composed of similar materials and resem- 

 ble each other in form ; and the various genuine 

 species of the genus V^espa construct cells, for the 

 most part, of the same figure, and employ the same 

 kind of materials (c); the mode of nidification, 

 tlierefore, should never be Assumed as characteristic 

 of a species, but after the most mature considera- 

 tion, and the closest and most attentive investiga- 

 tion of its history, economy, &c. for it generally 

 happens that those insects which agree together in 



(c) Reaumur, torn. 6. Mem, 6, 7. Tab. 14 — 25. 



habitj 



