658 DIPTERA OF AUSTRALIA, 



apparently not so numerously as the Cecidomyidse, but no peculiar 

 Australian genera have been yet detected ; with the exception of 

 one species which I refer to the genus Trichosia, Winn., all belong 

 to the typical genus Sciara, Meig. 



A large proportion of the species described in the following 

 pages were obtained by Mr. Masters and myself whilst searching 

 for Cecidoniyidae, and therefore the result cannot be regarded as 

 consequent upon very special research ; had the latter been the 

 case, the number would no doubt have been augmented ex- 

 tensively. 



My attention has been so completely occupied with the collection 

 and description of the perfect insects that little opportunity has 

 favoui'ed an investigation of the life-histories and young stages of 

 the Sciarid;«; however, I hope the time may not be long post- 

 poned when I shall be able to supplement this imperfect work 

 with accounts of these, but to ascertain the complete life-history 

 of individual species is alone the work of months. Meanwhile I 

 have given genei-al descriptions of the larva and pupa stages, 

 entirely summarized from the works of the few authors who have 

 at all sttulied them, and I hope that the information will tend to 

 direct the attention of students to this most neglected but deeply 

 interesting group, the species of which during the young stages 

 of their existence especially demand our consideration. 



In the descriptions I sometimes employ the words " apparently 

 no pubescence," by which I mean that no hair is made visible 

 through the application of an ordinary entomological lens, but is 

 rendered so when submitted to a working microscope of moderate 

 amplification ; indeed but for the latter even the longitudinal 

 rows of pubescence on the thorax of many species could not be 

 made out. I use the term " petiole " to mean that portion of the 

 third longitudinal vein between its origin and the base of its 

 fork ; and " fork " is always an abbreviation for fork of the third 

 longitudinal vein. 



