ORTHOPTERA. 



287 



vations on the development and habits of the very proHfic Blatta 

 Gernumica. It lays its eggs in a silky capsule, which is in the form 

 of a bean, with two valves in the interior. This is drawn about for 

 some time appended to the extremity of the abdomen, and after a 

 time abandoned. 



Hummel placed under a bell-glass a female cockroach and a 

 perfect egg-pouch, which had only just been abandoned by another 

 female. He saw the cockroach approach the bag, feel it, and turn it 

 about in all directions. She then took it between her front legs, and 

 made a longitudinal opening in it. As the opening grew wider, little 

 white larvae were seen to come from it rolled up and attached together. 

 The female presided at this operation. She assisted the larvae to set 

 themselves free, aiding them out gently with her antennae. In a few 

 seconds they were able to walk, when she ceased to trouble herself 

 about them. 



The larvae change their skin six times before reaching the perfect 

 state. When they come out of 

 their skin they are colourless, 

 but the colour comes in a few 

 minutes. At the fifth moult, 

 which takes place three months 



I after birth, they become pupae, 



j with rudimentary wings, the 



j whole shape of the insect being 



i well marked. The sixth, or last 

 moult, takes place at the end of 

 six weeks. The pupa is now 

 changed into a perfect insect. 



I The female is distinguished from 

 the male by the greater size of 

 her abdomen. 



The most destructive of the 

 Blattce, or Cockroaches, are those 



which have been imported into Europe by the ships coming from the 

 colonies. The Kaker lac Americana is from an inch to an inch and 

 a quarter long. It infests ships, running about at night over the 

 sleeping passengers, and devouring the food. They are to be met 

 with in all parts of the world. They abound particularly in the 

 warm parts of America. The Blatta orientalis is more commonly 

 met with than the above. It swarms in kitchens, in bakers' shops, 

 provision shops, &c., where it hides in the cracks of the vvalls, or 

 against the hinges of the doors. It is a small hideous animal, of 



Fig. 301.— The Cockroach {Blatta orientalis). 



