November, 1872.] 121 



DESCEIPTION OF A NEW QENUS AND TWO NEW EXOTIC SPECIES 

 OF THE FAMILY LARRID2E (SYMENOPTERAJ. 



BY C. E I T S E M A. 

 PlAGETIA, g. n. 



Head transverse, a little wider than the thorax, truncated and 

 excavated behind ; face a little prominent ; eyes large, oval, their 

 inner orbit straight ; only one well developed ocellus ; antennae fili- 

 form, inserted at the base of the clypeus at a little distance from each 

 other, the scape fully as long as the two first joints of the flagellum ; 

 mandibles notched exteriorly near the base, not (?) toothed within. 

 Prothorax narrower than the mesothorax, produced into a neck, which 

 is received into the excavation of the head, posterior margin bowed 

 backwards in the middle ; metathorax elongate, of about equal length 

 to the mesothorax, truncated posteriorly, the sides a little wider at the 

 base. Intermediate tibiae with a single spine at the apex ; posterior 

 femora with a stout, curved tooth ( (^ ) or with a little tubercle ( $ ) 

 at the base, flattened if not excavated beneath. Anterior wings with 

 one marginal cell truncated and appendiculated at its apex, and three 

 submarginal cells, the first longer than the two following, the second, 

 which receives both recurrent nervures before its centre, narrowed 

 towards the marginal cell, the third lunate. Abdomen a little shorter 

 than the thorax, heart-shaped, petiolate ; the first segment conical, 

 I and at the under-side (especially in the male) with a scale-shaped 

 transverse appendix ; the second segment the largest. 



The genus here described agrees with Larrada and Larraxena, 

 Smith, principally in having only one well developed ocellus (the pos- 

 terior pair being obsolete), and in the elongated and truncated meta- 

 thorax ; but it differs from them in having the first submarginal cell 

 longer than the two following united, a character in which it agrees 

 with Morplwta, Smith ; the latter, however, has the second submarginal 

 cell triangular, and three distinct ocelH. The neck-shaped prothorax, 

 the petiolated heart-shaped abdomen, and the armed hind femora, re- 

 move it from all the hitherto described genera of this family with 

 three submarginal cells. The genus Aulacophilus, Smith, which has 

 only two submarginal cells, has also a petiolated heart-shaped abdo- 

 men, but the petiole is longer than in Piagetia. 



P. WOEKDENI, sp. n. 



$ . Length 8 mm. Head black, antenna;, clypeus, cheeks, and mandibles ferru- 

 ginous, the latter black at the tips ; clypeus, cheeks, base of mandibles, and of the 

 exterior orbit of the eyes, thinly covered with short silvery pubescence, and the face 



