1917] Hungerford—Life-History of Mesovelia mulsanti White 81 
TABLE OF MEASUREMENTS IN MILLIMETERS OF INSTARS OF MESOVELIA MULSANTI. 
Antenne. Hind leg. Middle leg. Fore leg. 
Measurement 
r f tip of 
Stage. ae ne ; 
femur to tip} : 2 || A ‘ 
3) &0 40 o Le : = ix . Ls . 
of femur. 2h || PE Ba ay = & Z = S “B = Weebl | ae 
alee lee ale sates lee he 3 | 3 | 2) 3 
a a cs = is sal = ies e ic ae e 
Ist instar. ... ile 149] .099).11 |.416 AIG) so73|e2101> .3386) 1306) 2166) 225 (3213) 129 
2d oy 1.25 20) |=125}). 20) |\.5 54 {O25} pe2ol oo 343.188 312) .26 |.135 
3d ‘ RS 25 |.166|. 207) .54 625 85 |.275| .437 44% )\2220. |, o00l|,008 | Lou 
4th Z PASMPAN 29) 21 ||.382) 7 .81 | 1 .3875| .625) .625).29 i 38 |.25 
5th DEO 375|.29 |.375|.81 | 1.03 | 1.37 |.487| .75 RON eOnO) 625] .50 |.26 
thc ee eee rams feta: teers .65 |.416].716].96 | 1.35 | 1.56 |.5 1.09 | 1.09 |.416 858].75 |.26 
(Ant, (OP ER one] |AOeOARE BB eee EHO Son Oo son || laoOe | le OSm Goi ||P Leelivanle declgan lio 91 |.78 |.312 
Before attaining the adult stage, the nymph passes through five 
nymphal instars spending from two to three days in each stage. 
Mating occurs and oviposition begins about the third day. One 
female emerged August 1, began to lay August 3 and died August 
12, having laid 44 eggs an average of nearly 5 eggs per day. Some 
of the females in isolation laid an average of less than this, while 
one female under observation laid 18 eggs in 24 hours, a surpris- 
ingly large number, when we consider the size of egg and adult. 
The table presented on p. 82 is the history of one of a number of 
series, of isolation rearings, and indicates the variations in the 
duration of the different stages. The record of the many that 
died after isolation is omitted. It represents at least 90 per cent. 
of the total for mortality is very heavy under laboratory conditions. 
However, rearing in isolation and in close confinement is the only 
way to arrive at the number of molts and duration of instars. 
When a number are reared together the close resemblance of the 
instars and the variation in size within a given instar makes pre- 
cise observation impossible. The writer has endeavored to 
determine diagnostic characters for the various instars. In the 
apterous forms he has found the spread from tip of femur to tip of 
femur the only fairly satisfactory determination (see table above). 
The developing winged forms beginning with the third instar are 
readily placed. (See Fig. 3 for the size of the wing pads in the 5th 
instar.) 
