Monoyra2)h on the Syncnji of the Oalc-galh. 275 



a. Third joint of the antenna^ twice as long as the 

 fourth. Haimi. 



b. Third joint of tlie antenna? not twice as long as the 



fourth. undulatus. 



CEROPTRES. 



A. Face with two acute longitudinal keels. arator. 



B. Face with two obtuse and sometimes indistinct longitu- 



dinal keels. Cerri. 



List of the Flies whose Galls are inhabited by the 

 PRECEDING Species. 



1. . Synergus melanopus. 



Cynips argentea. Cynips polycera. 



„ hungarica. „ caliciformis. 



„ tinctoria. „ amblycera. 



,, Kollari. „ caput-medusa\ 



„ lignicola. „ calicis. 



„ conglomerata. Aphilothrix lucida. 



„ glutinosa. „ gennnoe. 



„ coriaria. „ elementing. 



2. Synergus Reinhardi. 



Cynips argentea. Cynips caliciformis. 

 „ tinctoria. „ caput-medusa?. 



„ Kollari. „ calicis. 



„ glutinosa. 



3. Synergus evanescens. 



Cynips calicis. Aphilothrix gemnue. 



Andricus niultiplicatus. 



4. Synergus pallidipennis. 



Cynips tinctoria. Cynips coriaria. 



„ lignicola. „ conifica. 



5. Synergus flavipes. 

 ])ryocosnuis niacroptera, 



