I I 8 HYMENOPTERA 



it being one of the strange facts of nature that these highly 

 endowed creatures never even see the offspring for whose welfare 

 they labour with such extraordinary ingenuity and perseverance. 

 Neither can we suppose that they have a conception of it 

 derived from a knowledge of their own individual history ; for 

 their very complete metamorphosis is scarcely reconcilable with 

 any such recollection on their part. It may possibly therefore 

 be the case that, having no idea whatever of the offspring, they 

 are equally destitute of any conception that it will be destroyed by 

 the operations of the Larrada. However this may be, Whittell 

 informs us that both wasps skirmish about for a little as if each 

 were mistrustful and somewhat afraid of the other ; this ends by 

 the Pelopaeus withdrawing its opposition and by the Larrada 

 taking possession of the cell, which it then proceeds to divide 

 into two, using for the purpose of the partition portions of the 

 material of the nest itself; possibly it is only a contraction of 

 the size of the cell, not a true division, that is effected ; however 

 this may be, after it is accomplished the Larrada deposits its 

 own egg in the cell, having, it is believed by Whittell, previously 

 destroyed that of the Pelopaeus. Judging from what occurs in 

 other species it is, however, more probable that the destruction 

 of the egg or young of the Pelopaeus is carried out by the larva 

 of the Larrada and not by the parent-wasp. From a remark 

 made by Maindron as to the proceedings of Larrada modesta, 

 in Ternate, it seems probable that its habits may prove to be 

 similar to those of L. australis, for it frequents the nests of 

 Pelopaeus after they have been completed. 



Sub-Fam. 4. Trypoxylonides. Differ from Larrides by the 

 inner margin of the eyes being concave, and the marginal 

 cell not appendiculate. (In Trypoxylon there is only one 

 distinct submarginal and one distinct discoidal cell, a second 

 of each being indicated faintly.} 



The nervuration of Trypoxylon is very peculiar, and differs 

 from that of the widely-distributed genus Pison, though according 

 to Kohl's views the two may be correctly associated to form 

 this sub-family. The species of Trypoxylon are apparently rather 

 fond of human propinquity, and build clay- or mud-nests in or 

 near houses. T. albitarse has this habit, and is well known in 

 Southern Brazil under the name of " Marimbouda da casa " 



