STRUCTURE AND ECONOMY OF SPIDERS. 3811 
on the right side divided, the former near the base 
of the humeral joint, the latter about the middle 
of the femur, and on the 15th of the succeeding 
month it cast its skin; yet, though all the other 
limbs were renewed, the stumps only of the mu- 
tilated members were reproduced. In cases in 
which spiders spontaneously throw off their legs 
at the articulation of the femur with the coxa, 
or have them partially removed by amputation, it 
would be desirable to ascertain in what state the 
limbs to be reproduced exist just previously to the 
act of moulting, as there is something mysterious 
in their extraordinary development during that 
process. 
I have since clearly established by dissection the 
fact that reproduced legs, immediately antecedent to 
the process of moulting, are curiously folded in the 
integument of the undetached portion of such muti- 
lated members. 
The dimensions of reproduced limbs are in inverse 
ratio to the extent of the injury previously inflicted 
on the parts; thus palpi and legs detached at the 
axillary joint and coxa are usually symmetrical, but 
diminutive, when reproduced ; while those amputated 
at the articulation of the digital with the radial joint, 
and near the middle of the tibia or the metatarsus, 
on being restored, are always very much larger and 
unsymmetrical : in point of fact, the development of 
the new limb depends upon the capacity of the unde- 
