578 PHILOSOPHY OF ZOOLOGY. 



males, females, and neuters, the last of which are apterous. 

 They live in societies. The Mutilladse have no neuters, 

 and the females are apterous as Mutilla, Dorylus, and La- 

 bidus. They are solitary. The others have the ocelli dis- 

 tinct, and are all furnished with wings. Among these there 

 are some families in which the wings arc always expanded. 

 In the Scoliadse, the first segment of the thorax is large, 

 and extends above to the base of the upper wings, as in 

 Scolia, Tiphia, Sapyga, Thymus, and Pampilus. In the 

 Sphexidse, the first segment of the thorax is narrow and 

 distant above from the base of the upper wings, as in 

 Sphex, Bembex, Larra, Crabro, and Philanthus. There 

 are other families in which the upper wings fold longitudi- 

 nally. In the Masaridae, the mandibles are narrow. There 

 are only males and females, which are solitary, as Hasa- 

 ns, Synagris, Eumenes, and Zethus. In the Vespadae, 

 which are social, as Vespa and Polistes, there are males, 

 females, and neuters ; and the mandibles are large. 



In nearly all the remaining genera, the hind legs are 

 made for carrying pollen, having the first tarsal joint en- 

 larged and compressed. Among these are some in which 

 the tongue, or intermediate process of the labium, is as 

 long or longer than its sheath, and deflected when at rest. 

 In the Apidae, which are social, there are males, females, 

 and neuters, as Apis, Melepona, Bombus, Euglossa, Euce- 

 ra, and Anthophora. While agreeing with the preceding 

 in many particulars, the following genera are destitute of 

 the expanded tarsal joint, for carrying pollen, Systropha, 

 Panurgus, Zylocopa, Geratina, Megachile, Phileremus, 

 and Nomada. Others have the tongue shorter than the 

 sheath, as the Andrenadae, including Andrena, Halectus ? 

 and Colletus. 



