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Regeneration in Argas persicus 
observations upon regeneration in the Arachnida and, so far as we are 
aware, none in the Ixodoidea. 
The present paper contains a short account of the regeneration of 
the limbs in Argas persicus. In a future communication we propose 
to describe also the regeneration of the mouth-parts. 
Historical. 
The first author to describe regeneration in an Arachnid was 
Lepeletier (1812), who noted that in spiders regenerated legs were 
normally jointed but shorter and darker than the other legs. J. Banks 
(1829) and Heineken (1829) also observed regeneration of spiders’ legs. 
Heineken noticed that after amputation of a limb the stump remained 
unchanged until the next moult, and then regeneration processes com¬ 
menced, extending through two or three moults. The same observer 
remarks that in fully grown spiders moulting and regeneration do not 
take place. 
Wagner (1887) observed that in the tarantula when a leg was 
removed at any place other than the coxa, the animal brought the 
wounded leg to its jaws and bit it off down to the coxa. 
In addition to the above, a number of writers have recorded the 
regeneration of the legs of spiders and the subject has been investigated 
experimentally by Schultz (1898) and Friedrich (190G). 
Schultz, working mainly with the Epeiridae, found that the leg was 
renewed if cut off at any level; in his experiments he generally removed 
the leg at the metatarsus, but also at the tibia, and usually at an 
articulation. 
Although these individuals, unlike the tarantula, never attempted 
to bite off any part of a wounded leg, yet when the leg was cut off 
at the coxa it regenerated better than when amputated at any other 
level. 
Schultz considers that this is an excellent example of the influence 
of natural selection, since regeneration takes place best at the point 
where the leg is most often broken off in nature. On the other hand, 
regeneration also takes place when the leg is cut off at any other point, 
thus showing that the power to regenerate is characteristic of all parts 
of the limbs and not merely a phenomenon of adaptation, for it is unlikely 
that a spider would ever lose a leg in the middle of an article, the 
joints being much the weaker. When the leg is cut off between two 
articles, the formation of the new part takes place somewhat differently 
