182 NATURAL ARRANGEMENT OF INSECTS. 



(159.) We enter the group of Fespidte by means 

 of Ceramius. This group appears to contain a well- 

 defined assemblage of insects, held together chiefly by 

 its tongue, furnished at the apex with glands, and the 

 lateral sweep of its prothorax. Other characters are 

 common to the normal genera, such as to the folding of 

 the superior wings longitudinally and the reniform eyes ; 

 but which are lost in some of the aberrant genera, such 

 as Ceramius, Masaris, and Paragia. The Fespides re- 

 solve themselves into solitary and social tribes, both ex- 

 hibiting a great variety of structure, and many genera : 

 we can only briefly notice the most conspicuous. The 

 majority of the males of these insects have the antennae 

 terminating in a recurved hook ; in others, this is re- 

 placed by that portion curling round ; and in others, there 

 are no means of distinguishing it from the same organs 

 of the female, but by the number of its articulations. 

 The typical Synagris exhibits a large horn affixed to the 

 base of the mandible of its male; and the same sex of 

 another species has two large curved spines placed be- 

 neath the second ventral segment. Abispa is apparently 

 the largest of the solitary wasps, and comes from New 

 Holland, whence we have yet seen no genuine Fespa, 

 the place of which, Mr. MacLeay says, is supplied by 

 this Abispa, the type of which is the Fespa Ephippium 

 of Fabricius, synonymous with the Ab. Australiana of 

 MacL. : the genus appears to consist of several species. 

 The resembling and numerous Rhynchium is very widely 

 distributed, as is also Odynerus, which is nearly related 

 to it. Eumenes, a solitary and numerous genus, con- 

 sists of large and usually gaily coloured insects ; it has a 

 very long petiole and pyriform abdomen. Zethus has 

 a long and exceedingly slender petiole. There is but a 

 slight distinction between Eumenes and some of the 

 exotic social genera, such as Epipona and other closely 

 allied insects. The distinction consists chiefly in the 

 form of the mandibles, which in Eumenes are very 

 elongate, slender, and forcipate ; whereas in the social 

 kinds they are more robust and dilated, and dentieu* 



