Rail — The Biology of Stagmomantis Carolina. 13 



sprightliness, leaving the sac still attached by the short 

 silken thread to the egg-case. The mantis as it leaves 

 the old skin is almost twice the size of the emerging 

 form, even though this entire process occupies but eight 

 to fifteen minutes from the moment the bead-like head 

 pushes through the trap-door to the time when the 

 nymph scampers away from the newly-shed covering. 

 The insects hang to the ootheca by means of the threads 

 for only a very few minutes and not, as Sharp says, "for 

 some days until the first change of skin is affected." 

 When one views the shrivelled little sac left hanging 

 from the egg-cell, one marvels that it really was sufficient 

 to cover the entire insect. The length just at emerging 

 is about 5 mm., and a very few minutes later, after the 

 envelope has been removed, it has increased to about 

 twice this size. 



The eggs all develop in their cells with the part which 

 forms the head nearest the exit, so the emerging insect 

 will have little difficulty in pushing its way through. 

 Either the eggs must be deposited right end up along 

 with the making of the case, or the egg-mass in the early 

 stages of its development must turn about in the shell 

 and thus come to a proper position. Gravitation can- 

 not be the controlling agency in this case, because the 

 egg-cases are built at all angles with the direction of 

 the force of gravity. Out of eighty egg-cases observed 

 during two years, I found only one exception to this po- 

 sition of the egg. In this instance, while many tiny 

 heads were appearing all over the crest of the case, 

 from one cell the caudal end of the body and a pair of 

 tarsi appeared. The nymph made a brave struggle to 

 emerge, but after a few minutes it was found dead. 



The Moulting Peocess. 



How often the mantis moults is not precisely known. 

 Howard (1901) says it moults at least three times; most 



