IIYMENOPTERA. 



593 



2. Polyergus, L3itr.,vih\c\iisa.lso destitute of a stingy, but with the antennas inserted near the mouth, and the man- 

 dibles narrow, curved, or very much hooked. P. rufescens, the Amazon Ant above described, not yet discovered in 



this country. 



3. Poiiera, Latr., the neuters and females armed with 

 a sting:. Peduncle of abdomen formed of a single knot ; 

 antennae in these individuals thickened at the tip ; mandi- 

 bles triangular ; head subtriangular. P. contracfa, Latr., 

 a very small species, [first discovered in England by me] 



Odontomachus, Latr., has the peduncular node spined 

 above ; the antennae of the neuters filiform ; the head 

 oblong, and deeply emarginate behind ; and the mandibles 

 long and narrow ; all the species are exotic. 



4. Myrmica, Latr., has also a sting, but the peduncle 

 of the abdomen is composed of two knots : the antennae 



Fie. 119.— A. Fonuica fusca and its Jaws ; B, Polyergus rufescens and ... •,, , • ■ j „ ■ ■ ^ , j 



itsjawi. exposed; the maxillary palpi long and 6-jointed; and 



the mandibles triangular. F. rubra, [misprinted rufa by Latreille], Linn., a very common British species. 



Eciton, Latr., differs from Myrmica only in having linear mandibles. 



Atta, Fabr., differs from Myrmica only in having very short palpi ; the head 

 of the workers is generally very thick. A. cephalotes. Fab., the Visiting Ant 

 of the West Indies, above mentioned. 



Cryptocerus, Latr., furnished with a sting, with the peduncle of the abdomen 

 formed of two knots ; the head very large and flat, with a groove on each side 

 to receive the antennae. South American insects, [monographed by Klug]. 

 [The excellent monograph of the ants by Latreille, and, as relates to their 

 habits, the memoirs of Huber, ought to be consulted in this family.] 



Fig. 120.— Atta cephalotes. 



The Other Heterogyna are solitaiy in their habits, each species being 

 only composed of winged males and apterous females, the latter always 

 armed with a powerful sting ; the antennae are filiform or setaceous, vibratile, with the first and third 

 joints elongated ; the length of the first never equalling one third of these organs. They form the genus 



MUTILLA, Linn. 



Some, of which males have only been observed, have the antennae inserted near the mouth ; the head small, and 

 the abdomen long and nearly cylindric. Genera, Dorylus, from Africa and India, and Lahidus, from South 

 America, [to which must be added two others, described by Mr. Shuckard in his monograph on these genera, pub- 

 lished in the Annals of Natural History, May and June, 1840]. 



The others have the antennae inserted near the middle of the face ; the head is more robust than in the preceding, 

 and the abdomen either conic or ovoid. These form the genus Mutilla proper, the species of which are found in 

 hot sandy districts. The females run quickly, and always on the ground. The males often alight upon flowers, 

 but we are ignorant of their precise economy. 



Some have the thorax nearly cubical, and not nodose in the females. 



Apterogyna, Latr., has the two basal segments of the abdomen in the form of knots ; the male antennae are very- 

 long ; the fore-wings have only basal cells, and a single cubital small and rhomboidal cell. [Exotic insects.] 



Psammotherma, Latr., has three cubital cells, with two recurrent nervures ; and the males have the antennae 

 pectinated. {Mutilla flabellata, Fabr., Cape of Good Hope.] 



Mutilla proper, has also three cubital cells, with two recurrent nerves, but the antenna: are simple in both sexes, 

 and the second segment of the abdomen does not form a knot. Type, Mutilla europaa, [a rather common British 

 species]. 



Myrmosa, Latr., differs from the preceding in having the thorax in both sexes equal, but divided into twodistinct 

 segments, with the abdomen conic in the females. 



Myrmecoda, Latr., has the thorax of the females also equal above, but divided into three segments by sutures, 

 and the maxillary palpi very short. [These insects are now proved to be the females of the genus Thynnus, placed 

 by Latreille in the family Scolietes.] 



Scleroderma, Klug, differs only in the maxillary palpi being elongated, and the antennae has the second join 

 not inclosed in the tip of the preceding. [Small continental species. See my monograph on this genus, published 

 in the Transactions of the Entomol. Soc. of London, vol. ii.] 



Methoca, Latr., has the thorax nodose. [M. ichneumonides, a very interesting insect, found but rarely in this 

 country, resembling an Ant, and now proved to be the female of the genus Tengyra, placed by Latreille in the 

 next family.] 



THE SECOND FAMILY OF THE ACULEATED IIYMENOPTERA,— 



The Fossores, — 



Comprises those aculeate Hymcnoptera which have all the individuals winged, and of two kinds onlv 



[males and females], and which live solitarily, their legs being fitted only for walking, and in many for 



a Q 



