Special Protection of Appendages among Insects. 501 



I^XVl. — On the Spfc'uil Protrrfitin of Appenihigos in Procesa 

 of Regenei-ation dfler Artijiridl Mutihition mnong Insects. 

 \\y Edmond Hordage *. 



^^'n^:\ a limb is removed owing to self-mutilation from the 

 body ol an Artliropod, such as a crab or a Phasmid for in- 

 stance, regeneration starts from the very surface of the 

 section so produced. The same thing, however, rarely 

 hapjiens when, on the other hand, regeneration follows the 

 artificial severance of a limb. Among Mantida3, Blattida^f, 

 and the Orthoptera saltatoria, for example, artificial cuts are 

 followed by contraction and by more or less marked displace- 

 ment of the divided muscles, which are retracted within the 

 chitinous covering of the limb, so that, if regeneration follow, 

 the part in jirocess of growth remains entirely hidden until 

 the next moult. The chitinous case therefore in this instance 

 plays the |)art of a jirotector. 



It may even happen among the Mantidir, which possess the 

 power of self-mutihition developed in a high degree, or among 

 the Blattidre, where it is much less marked, that contraction 

 of the muscles may be produced in the interior of the tro- 

 chanter, or even inside the joint, if developed, that forms the 

 haunch (roj-a), after self-mutilation along the trochantero- 

 femoral suture. In this case, if there be regeneration the 

 part in process of growth will remain hidden until tlie next 

 moult. 



Most often, however, among the Mantids, and more rarely 

 in the Blattidse, this contraction does not take place after 

 self-mutilation. 



In this case one can very soon see whether there will be 

 regeneration without its being necessary to wait for the next 

 moult. It is true that one cannot perceive the various parts 

 which make up the rudiment in process of growth, for it is 

 coiled upon itself, and, what is more, covered over by tho 

 non-chitinized cuticle, which protects it after the manner of 

 a pocket. This cuticle lacks transparency on account of its 

 brownish coloration ; but the very slightly marked projection 

 which this protective pouch forms at the end of the trochanter 

 shows nevertheless that the work of regeneration is going on. 



In the Phasmidai the rudiment in process of growth destined 



* Translated from ' Coinptes Rendus,' cxxix. (1890) pp. r)01-i>04, by 

 Wilfred Mnrk Wi'l)b, F.L.S. From a si-parate impression coiiiniuni- 

 cattil liy tlif Autlior. 



t II. II. iJrindii'v, ' On certain Character-' vX luproduced Appendaj^es 

 ill Arthrnpoda,' 1898. 



