CHRYSOPS (MEIGEN) , EARLY STAGES IN GENERAL. 



In Fabricius' Systema Entomologies and Eniomologia Systematica 

 I have found no statement of the early stages of any species of this 

 genus. 



Zetterstedt says that, according to Fabricius, the larvae live in the 

 ground. However, Zetterstedt himself saw a large number of appar- 

 ently new emerged adults at the borders of a lake, which would 

 indicate an aquatic habitat. 



According to Hart, the larvae and pupae of Chrysops, as well as the 

 imago, are distinguishable from those of Tahanus by the antenna! 

 structure. Otherwise the Chrysops larvae closely resemble in 

 structure small or young Tahanus larvae. The dull pubescent annuli 

 are partly present in Chrysops, but the longitudinal lateral lines, ex- 

 cept on the prothorax, are shining and almost entirely without pu- 

 bescence. There is very little pubescence here, however, in some 

 young Tahanus larvae. The species described by Hart {Chrysops 

 vittatus Wied.) is easily recognized by the dark patch on the last 

 segment. 



The distinguishing characteristics given for larvae of Chrysops 

 compared with those of Tahanus are the following: "Last antennal 

 joint much longer than the one preceding, dorsal areas of thorax 

 striated like those of abdomen." Neave compared the syphon of the 



consequently take the place of the auditory hairs which are missing, and as the 

 pedunculate bodies, which in reality are modified hairs, would assume the func- 

 tion of otoHths, there would be no exception to the general rule that true oto- 

 liths are not found among insects. Functionally the organ could well belong to 

 the group where it was placed by Graber. Also the fact remains that, even 

 according to Paoli, nerves go to the fundus of the cj^st, where the pedunculate 

 bodies are attached. The problem cannot be regarded as solved by Paoli's 

 hypothesis. On the other hand, to assume a true auditory function seems equally 

 hazardous; it seems more probable that the organ might play a part in the senses 

 of equiUbrium and orientation, which, however, can only be determined by 

 further investigation. 



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