82 
more abundantly late in the year than earlier in the season. During 
the last week of November larvae have been seen nearly grown, with 
about an equal number of pupae at the same time. Moths captured 
then deposited eggs even in a quite cold temperature. As with the 
imported cabbage worm, most larvae transformed to pupae during the 
first week of December. Moths began issuing from this lot December 9. 
An interesting feature in connection with the late occurrence of this 
species was the presence at the same time of one of its most active 
parasites, an Ichneumonid Limneria tibiator Cr. These parasites 
began issuing the same time as the moths just noted, showing that the 
enemy has about the same time of appearance in the fall as its host, 
and perhaps this is the same in the spring. Such coincidence in the 
time of occurrence of a parasite and its host, however, the writer 
believes to be rather exceptional. 
Moths were seen on a warm day, December 13, fiVing in the sun- 
shine. This was after three or four days of very cold weather. 
Nearly eveiy head of cabbage that was touched was found to harbor 
one or more moths, while others were flying about other vegetation of 
the vicinity. At no time during the entire }^ear were moths seen in 
anything like the same abundance as at this time in mid-December. 
Larvae and pupae were also observed. 
The Harlequin Cabbage Bug (Murgantia histrionica Hahn). — This 
insect was exposed to the same atmospheric conditions as the preceding- 
species, and was observed feeding with them until late in November. 
When fields were visited during the middle of December, however, 
none of the bugs were to be found in exposure upon the plants, although, 
as has been said, the diamond- back moth was flying freely in the bright 
sunshine. Under leaves which touched the ground some specimens 
were found, and such stalks as were pulled up and shaken showed that 
many of the bugs had crawled in between the leaves into protected 
places. They were dislodged in some numbers, two score and more 
being found in single large heads. When the infested cabbage fields 
were visited a month, later it was seen that the more severe frost which 
had occurred during the month had killed great numbers. By gather- 
ing numbers of the bugs and taking them home for counting, an 
estimate was made that 85 per cent had been killed. Cold spells which 
followed afterwards doubtless killed many more. 
As a result of study of this species for several seasons, it has been 
ascertained that the bugs do not, as a rule, issue from hibernating 
quarters until near the end of April. Eggs were first noticed on the 
28th of that month, but in some seasons the bugs may lay earlier. The 
first imagos of the new brood have been observed to develop during 
the last week of June, the 26th being the first observed date of their 
development. The second generation usually begins to develop about 
the beginning of the third week of August. 
