706 Wisconsin Academy of Sciences, Arts and Letters. 
As mentioned by McLachlan for the genus, the wing venation 
varies greatly as between species, and is quite variable m a sin¬ 
gle species, or, even in individuals, the two sides being often 
unlike. I have given what appears to be the typical venation 
of the species. 
Larva. —Length, 13-14 mm. Width, 2.5 mm. Body in life 
green. Head yellow, with a band of black along the sutures of 
the clypeus and the median dorsal suture of the head; the stem 
of this “Y” does not extend over the prethorax as in M. cinerea, 
but may have that appearance if the head is strongly retracted. 
The occipital foramen is bordered with brown; gula dark 
brown. Prothorax with a broad dark brown border posteriorly 
-and laterally. Anterior portion of the mesothorax separated 
from the posterior part by a transverse white line, which curves 
forward and outward; the darker brown anterior portion thus 
delimited is divided by a median line of white; the posterior 
part is irregularly clouded with lighter brown. Metathorax not 
chitinous. Legs yellow, the anterior femur bordered with 
brown. Lateral line on segments 2-8, the short, close-set hairs 
Being replaced on the 8th by chitinous points followed by sev¬ 
eral long hairs distinctly separated. Labrum not heavily 
chitinized, yellow. Antennae yellow, placed very close to bases 
of mandibles. Gills branched, Fig. 14. 
Pupa. —Length, 13 mm. Width, 2.5 mm. Antennae extend¬ 
ing to the 8th segment. Body in life light green. Dorsal 
spines, III, 3. 4. 4 + 4-5. 4-5, VI. Lateral line begins on 
3rd segment and forms a loop under the 8th. Gills appear to 
be as in the larva. Body terminated posteriorly by two straight 
finger-like projections studded thruout their length with short 
spines and ending in two long hairs. Mandibles long, serrate 
within, the tips incurved, hook-like. 
