52 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 9 



females coinnionly outlive the males, sometimes several weeks, when 

 they deposit their eggs and die. This large species is a very voracious 

 feeder from the time it reaches the second instar until maturity and 

 death. It will even feed on its own mates when crippled or in 

 any way unal)le to protect themselves. This is especially noticeable 

 when molting, for at this time the insect, for a short period, is prac- 

 tically helpless. Their food consists mainly of caterpillars of various 

 kinds. For a short period records were kept of the numbers of cater- 

 pillars these insects would kill. My first experiment was with a 

 male and female. Following is the record of the caterpillars killed by 

 the two insects between July 24 and August 17, 1913: 



July 24 Datana integerrima 4 caterpillars 1 inch long. 



July 26 Halisidota caryce 4 caterpillars 1 inch long. 



Aug. 4 Datana integerrima 4 caterpillars 1 inch long. 



Aug. 8 Datana integerrima 4 caterpillars 1 inch long. 



Aug. 11 Dala7i.a integerrima 4 caterpillars Nearly full grown. 



Aug. 16 Callosamia promethea 1 caterpillar If inches long. 



In another feeding experiment, using two adult males, between July 

 24 and August 15, 23 caterpillars were killed. 



July 24 Datana integerrima 4 caterpillars 1 inch long. 



July 30 Datana ministra 4 caterpillars Full gro^\ii. 



Aug. 4 Achemon sphinx 1 caterpillar Full grown. 



Aug. 8 Datana integerrima 6 caterpillars Full grown. 



Aug. 11 Datana angusii 4 caterpillars Full grown. 



Aug. 15 Datana integerrima 4 caterpillars Full grown. 



Apateticus maculivcntris Say 

 These insects commence laying eggs under ordinary climatic con- 

 ditions the latter part of May, or early June. The eggs are of a brown- 

 ish-black color with a metallic luster, and measure about one-sixteenth 

 of an inch in height and about one-third less across. They are oblong, 

 oval in form, each being somewhat tapered at its base or at the point 

 at which it is cemented either to leaf or bark. The top of the egg is 

 quite broadly rounded, surmounted by a cap, around which is a circlet 

 of about fourteen hair-like spines. At the time of hatching, this cap- 

 like structure is pried open by the emerging insect. The number of 

 eggs laid by a single individual varies to some extent. Commonly, 

 the egg-laying period extends over two or three weeks, during which 

 time the female deposits several clusters of eggs at intervals of a day or 

 two between each laying. My records show that some insects deposit 

 but three groups of eggs, while the greatest number was nine, deposited 

 between June 28 and Juty 17, 1913. The most common number of 

 eggs deposited at a single time is from 20 to 30. Thirty-five eggs is 



