18 Trans. Acad. Sci. of St. Louis. 



In 1910 the first adult female appeared on Aug. 16. 

 In 1909 the first gray female came to maturity on Aug. 

 3 and the first green one Aug. 9. All these were taken 

 in the open, where development would probably be a 

 little more rapid than in confinement. 



The nymphs of the two sexes are very similar and 

 cannot be distinguished by appearance until the instar 

 just preceding adulthood. In the adults, the difference 

 in the size and shape of the bodies is so great that they 

 might easily be mistaken for two distinct species. The 

 male has a long, slender body completely covered by the 

 wings; the body of the female is much broader and the 

 wings are aborted so that they cover only a part of the 

 body. 



Method of Shedding the Skin. 



The method of moulting is the simple one character- 

 istic of most Orthoptera. The skin splits along the 

 prothorax and the insect works its way out; usually the 

 head and prothorax are pushed through the opening 

 first, and the abdomen and legs are freed later. Fre- 

 quently the smaller nymphs hang with the hind pair of 

 tarsi interlocked around a twig while undergoing this 

 metamorphosis. 



In PI. XVIII, Fig. 2 we see a twelve-day insect (% 

 natural size and enlarged) undergoing its first real ecdy- 

 sis. The body is wholly free and the insect is struggling 

 to extricate its legs from the old skin. Pis. XI, XII, XIII 

 show the nymphs after the fourth moult, when the wing- 

 pads are first apparent. 



The mantis all hatch at about the same time and, 

 when the insects are free in nature, the whole population 

 seems to moult at about the same perid, so the rate of 

 development of all the individuals is kept about parallel. 

 In other words, when one finds mantis, say in June or 

 September, they are almost always all very much alike 

 in size and form. Hence we do not find, as Rathvon 

 (1862) records, that the "mothers often feed upon their 



