ORTALID^E — INTRODUCTION. 5 



stricken out, or at least to be modified, in order to leave, as a 

 residue, the true characters of the family Ortalidae. 



Here also I begin with the European fauna, as the genera 

 and species composing it are by far the best known. 



The variously organized groups of species, within the genus 

 Ortalis, each have, outside of this genus, a circle of relation- 

 ship of their own. 



1. Forms reminding of Ortalis lamed. 



If we begin with Ortalis lamed (pulchella Meig.), we are led 

 at once towards Sciomyza bucephala Meig., which Macquart 

 has united, with several other heterogeneous species, in the 

 genus Otites, and for which I have later established the genus 

 Cormocaris. 



Cormocaris brings us to Tetanops, which agrees in its prin- 

 cipal characters with Cormocaris bucephala, quite erroneously 

 placed in the genus Sciomyza by Meigen. In this species, as 

 well as in all the European species of Tetanops which I know 

 of, none of the characters are wanting the presence of which 

 distinguishes the genus Ortalis. 



The genus Tetanops again leads us towards Dorycera ; the 

 remarkable elongation of the second antennal joint is a peculiar, 

 character of most species of this genus, a character not to be 

 found in the species of Ortalis. However, the difference in the 

 length of this joint in different species of Dorycera sufficiently 

 shows that too much systematic stress ought not to be laid upon 

 this character ; all the other characters agreeing with those of 

 the Ortalidae, Dorycera must necessarily be placed in this 

 family. 



Next to Dorycera I find the genus Adapsilia, founded by 

 Waga, which, like most Dorycerse, has an elongated second an- 

 tennal joint. It is distinguished by a very projecting front, 

 very approximated antennae, and the want of ocelli ; with the 

 species of Ortalis it agrees in the characters already specified, 

 except that the first joint of the ovipositor of the female is not 

 flattened, as in all the species of Ortalis, but capsule-shaped, 

 swollen ; as, however, in other respects the structure of this 

 ovipositor resembles that of Ortalis, Adapsilia must also be 

 added to the Ortalidse. At the same, time, the statement con- 

 cerning the shape of the ovipositor of this family must be some- 

 what modified to be applicable to Adapsilia. 



