June, ’20] 
SATTERTHWAIT: HABITS OF CALENDRA PERTINAX 
285 
dead pupae, 2 hymenopterous parasite cocoons, 5 adult exit holes, and 
a lost top to 1 larval excavation, the top having been removed in the 
swamp. Of these, 10 larvae and 1 pupa appeared to have been drowned. 
Thus, of 23 specimens actually accounted for,—18 dead and exits pre¬ 
sumably of at least 5 adults,—about 8 per cent of the mortality is 
parasite, about 48 per cent apparently drowning, 22 per cent not 
accounted for, and only about 22 per cent of the brood successfully 
matured. So far as life permitted, pupation in this series was entirely 
within the plants. The series of 12 stalks from the portion of the 
swamp not water-covered showed 16 burrows, 3 dead larvae (2 killed 
by hymenopterous parasites but none apparently by drowning), 2 
living and 3 dead pupae (1 killed by a hymenopterous parasite), 2 
adult female C. pertinax, 3 hymenopterous parasite cocoons and exits 
presumably of at least 5 adults. Only 1 of the 12 stalks showed a 
portion of a crown. Had the complete crowns been secured, more 
excavations and possibly, though improbably, some evidence of soil 
pupation might have been found. Thus, of 15 specimens actually 
accounted for,—6 dead, 4 living and present, and exits presumably of 
at least 5 adults,—60 per cent have matured or probably will mature 
successfully, with 20 per cent mortality attributable to parasites and a 
like mortality to undetermined causes. 
In conclusion to the study of the C. pertinax habits in the Flushing, 
N. Y., conditions, it may be stated that pupation has occurred inva¬ 
riably in the cat-tail stalk, at or near the top of the larval excavation, 
that adults developed in the swamp as early as September 6, and in 
cages as early as August 19 from a pupa collected August 10. In the 
collections of October 13, 1919, of 38 specimens accounted for in 24 
stalks, 12 adults had matured fully and only 2 remained immature, 
these 2 being pupae with a fair possibility of maturing before winter. 
Numerous eggs were present August 10, 1919, while pupae were present, 
indicating a possibility that some might not mature before winter, 
hence explaining the condition that Mr. Bell found at Flushing in 
March, 1919, when larvae and pupae, as well as adults, were present. 
One point accomplished in the long egg-laying period of C. pertinax 
is the avoidance of the obliteration of a colony by any probable single 
rise of water level. Eggs laid from the middle of June to the middle 
of August are likely to be laid in part at every normal water level, while, 
in the event of the water level rising only after the last of the eggs have 
been deposited, those first laid at low water levels will have had time 
to mature and the adults escape. 
The Situation in Indiana, Maryland and Missouri 
The places in Indiana, Maryland and Missouri from which C. per¬ 
tinax used in this study have been collected are West LaFayette and 
