ORTALID^S — INTRODUCTION. 1 3 



terculus, serpentinus ; the greatest part of the residue are species 

 which may be left in the genus Dacus. 



On the other hand, Wiedemann has placed in the genus Try- 

 peta several species which do not belong to the Trypetidse at 

 all and have all the characters of the Ortalidse. Such species 

 are : Trypeta ocellata, which Macquart described again as a 

 supposed new species, under the name of Platystoma ocellata, 

 and upon which Rondani established later the genus Pterocalla; 

 Trypeta obscura, which is very closely allied to the former, and 

 which Macquart very improperly placed in the genus Campto- 

 neura, while its place is in the genus Pterocalla, next to P. 

 ocellata; moreover Trypeta picta, the typical species of the 

 Ortalideous genus Gamptoneura : Trypeta Jlexa, which may be 

 placed in the genus Mischog aster ; Trypeta trimaculata, rede- 

 scribed by Macquart as Coelometopia ferruginea ; Trypeta cy- 

 anogaster, basilaris, scutellaris, and perhaps several others 

 among Wiedemann's Trypetse, which I have not had the occa- 

 sion to compare. 



Those species which Wiedemann placed in the genus Platy- 

 stoma, with the exception of his Platystoma decora, really belong 

 to that genus, and consequently to the Ortalidse. Platystoma 

 decora, which induced Macquart to establish the genus Loxo- 

 neura, is also to be placed among the Ortalidse. 



Tetanops sanguiniceps was described by Wiedemann from a 

 specimen of the Berlin Museum ; I have seen this species, unless 

 my memory deceives me, not in the Berlin Museum, but in Wiede- 

 mann's collection. I found that in the structure of the head 

 and in the venation it does not sufficiently agree with the Euro- 

 pean species of Tetanops to be left in the same genus with them, 

 but, at the same time, that it undoubtedly belongs to the family 

 of the Ortalidse. I am sure that the Dichromyia brasiliensis 

 of Rob. Desvoidy, described as the type of the new genus Di- 

 chromyia, is the same species. 



The Scatophaga bispinosa Fab., placed by Wiedemann in the 

 genus Tetanocera, differs from the other Ortalidse in the vena- 

 tion as well as in the shape of the scutellum very much, but 

 nevertheless, judging from Wiedemann's statements, and espe- 

 cially from his figure, it undoubtedly belongs in that family, 

 where Macquart also places it in establishing for it the genus 

 Notacanthina. Should we judge, however, from Macquart's 



