DIVISION OF THE FAMILY INTO TRYPETINA AND DACINA. 51 



ever striking the difference may be between the greatest part of 

 the species of Trypeta and the larger naked species of Dacus, yet 

 some of the latter approach very much to the larger species of 

 the polymorphous genus Trypeta, and show the near relation of 

 both genera. Wiedemann, misled by some Trypetce, had become 

 uncertain about the limits between the genera Dacus and Trypeta, 

 or he would not have placed the large Brazilian Trypeta parallela 

 among Dacus. One of the surest marks for separating both gen- 

 era is furnished by the structure of the female abdomen, which in 

 Trypeta shows five, in Dacus four segments before the borer, the 

 fifth being very short and concealed under the fourth. None of 

 the other characters, however marked they may appear, is so con- 

 stant as this. Macquart has already justly observed that the 

 whole of the first group of Dacus Wied. is not only a stranger to 

 this genus, but cannot even remain in the same family with it; 

 therefore giving it the generic name of Senopterina (which must be 

 mended into Stenopterina}, he assigned it its right place in the 

 Ortalidce, as will be detailed in the sequel. Among the new gen- 

 era introduced by Macquart, Leptoxys and Enicocera, perhaps also 

 Cardiacera, may be very nearly related to the genus Dacus, which 

 cannot be, however, asserted positively, on account of the insuffi- 

 ciency of Macquart's statements and the incorrectness of his figures. 

 The genus Bactrocera, founded by Guerin, seems also to belong 

 here. The same, perhaps, may be said of the genera Rioxa and 

 Strumeia, formed by Walker in the "Proceedings of the Linnean 

 Society," while the genus Dasyneura of Saunders, which Walker 

 in the "List of the Diptera of the British Museum" places near 

 Dacus, seems to stand much nearer to Trypeta. 



The species of the genus Trypeta and those smaller genera which 

 either have been comprised in Trypeta or founded in its neigh- 

 borhood, together with the species really belonging to Dacus and 

 the smaller genera subordinate to or co-ordinate with it in a simi- 

 lar way, form the family Trypetida, one of the group of closely 

 related families of the Acalyptera which are characterized by their 

 corneous ovipositor. 



2. Division of the family into TRYPETINA and DACINA. 



A division in two groups may be established as above indi- 

 cated. The two groups would be : Trypetina, with five distinct 

 segments of the female abdomen, and Dacina, with apparently four 



