136 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



throws it out of the shell. Now the way is free; the little one can 

 come out either by breaking the skin set in the opening or by throw- 

 ing it over, or else by finding the way out when the bursted bubble 

 has detached itself from the egg. It is simply marvelous! To come 

 out of its coffer the pentatomid has invented the mitre and the push of 

 of the hydraulic ram. The reduviid has constructed the explosive 

 engine. 



This performance, going on in the egg at the time of hatch- 

 ing, acts as another style of an egg-burster and is accom- 

 plished evidently by the air pressure within. For further in- 

 formation on this subject one ought to read Frederick Knab's 

 instructive paper on "The role of air in the ecdysis of in- 

 sects," published in volume xi of the Proceedings of our 

 Society. 



Eggs of the family Phymatidae (== Macrocephalidae) are 

 evidently related to those of the Reduviidas. They have the 

 same peculiar chorial processes, which are attached to the 

 inner side of the egg-rim, instead of standing free upon the 

 outside. (See fig. 1, b. ) 



Phymata erosa, subsp. Jasciata.* Egg, oval and stout; 

 length 1.6 mm., covered with a sticky secretion nearly up to 

 the neck; apical cap present, very thin and flat; outer sur- 

 face of the chorion coarsely granulated, color black; chorial 

 processes form numerous small channels on the chorion inside 

 the extension of the rim. (PI. X, fig. 5.) 



Since studying the different types of egg forms, the writer 

 has come to the conclusion that the family Tingitidse ought 

 really to be placed in the Reduviidae group, after the Phyma- 

 tidse. The tingitid eggs have very much in common with the 

 eggs of the Reduviidse; they possess channel-formed chorial 

 processes inside the extended rim of the egg-shell, and have 

 also an apical cap. 



The original description and figure of a tingitid egg of 

 the species Corythuca arena ta, was published by Comstock. 1 

 Later Morrill 2 in his exact paper "On the immature stages of 

 some tingitids of the genus Corythuca" pointed out the marked 

 difference in the manner of depositing the eggs existing be- 

 tween the oak tingitid, that of the hawthorn, and that on the 

 buttonwood. 



In the Tingitidse the depositing of the eggs occurs always 

 on the underside of the leaves. In some species they are par- 



5 G. C. Champion, Biol. Centr. Amer., vol. II, p. 50 (1901.) 

 1 J. H. Comstock, Rep. Comm. Agri. 1879, 1880, p. 221. 

 2 C. A. Morrill, Psyche, 1903, p. 127. 



