70 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



and brought together all that was known regarding the role 

 of air in the ecdysis of insects.* The studies of Kunckel d' 

 Herculais were largely made upon an injurious locust of 

 Algeria (Stauronotus uiaroccamts Thunberg) and similar 

 conditions were found by him in other Orthoptera. In the 

 acridiids observed by him the air is employed during each 

 successive moult and furthermore by the female at the time 

 of oviposition. Moreover the air plays an important part in 

 the escape of the newly hatched young from the egg-cocoon. 



The young locust possesses, dorsally, between the head and 

 the prothorax, a bladder (ampoule cervicale) which can be 

 inflated or retracted. Six or seven of the newly-hatched locusts 

 direct their efforts against the lid of the egg-cocoon and by 

 means of their cervical bladders force it off. Such is the pres- 

 sure thus exerted that the lid of the cocoon sometimes flies 

 several centimeters. The cervical bladder is further employed 

 when the young locust works its way through the crevices in the 

 ground to the surface. By inflating and retracting this organ 

 it is able to vary the dimensions of its body in such a manner 

 that it can squeeze through crevices that would otherwise be 

 impassable. When the young locust has reached the surface 

 of the ground it casts its first skin and here the cervical bladder 

 is again brought into service to rupture the skin. To inflate this 

 cervical bladder blood is forced into it from the body cavity 

 and this is accomplished by the agency of air. The air is taken 

 into the digestive tract directly by swallowing until the crop 

 becomes greatly inflated, and by this means the blood is pressed 

 into certain parts of the body. Kunckel d'Herculais also 

 found that at the time of moulting the tracheae are not filled 

 with air and therefore the tracheal system takes no part in this 

 process. 



As before stated this mechanism is again employed at each 

 moult. In the last moult the wings are expanded by blood 

 forced into them by the same means, that is, the inflation of the 

 digestive tract with air. Lastly in the female the air performs 

 an important function during oviposition, as by its means the 

 abdomen is forced into the ground. This was discovered 

 through the fact that a locust with an abdomen 5 cm. in length 

 is able to bore a hole into the ground 8 cm. in depth. The air 

 taken into the digestive tract greatly distends the abdomen and 



*Mecanisme physiologique de 1'eclosion des mues et de metamorphose 

 chez les Insectes orthopteres de la famille des Acridides. Compt. rend. 

 Acad. Sci. Paris, v. 110, pp. 657-659 (1890). 



Du role de 1'air dans le mecanisme physiologique de 1'eclosion, des 

 mues et de la metamorphose chez les Insectes Orthopteres de la famille 

 des Acridides. Compt. rend. Acad. Sci. Paris, v. 110, pp. 807-809. 



