NEMATOCERA. 41 
under the microscope, and impossible to count them. Only a rough 
sketch of the balancer is therefore given here, the bulb being the 
part which joins the body, and some groups and rows of vesicles 
being indicated in the narrower part. 
The males are smaller than 9, and their abdomens have knotty 
pincers (Fig. 8) ; the females have pointed projecting ovipositors. 
Fic. $--3 Geaita'va of a Cecid. 
Larvee, fourteen-ringed, become pupz within the larva skin, or 
are uncovered,* 
These characters are sufficient to separate the Cecidomyide. 
The limits, however, between this family or “gall gnats,” as they are 
popularly called, and the “Fungus gnats,” or ALycetophilide, cannot 
be easily fixed, the genus Zygoneura, for instance, bridging over the 
two families, this genus showing combinations of characters found in 
both families; the cox being far less elongated, and the spurs of 
the tibize far shorter than in the AZjcetophilide. Besides this, they 
have undoubted Cecid characters in the antennz, which are monili- 
form with verticillate hairs, a character never found in “fungus- 
* Winnertz figures larvee of C. Urtice and Tremule (Lin. Ent.), Pl. L., 1 and 2. 
