8 
INTRODUCTION. 
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 of 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 undetached portion 
of the mutilated part; for if a leg be amputated near the middle of the metatarsus, the coxa, 
femur, and tibia will be of the same dimensions as those joints of the corresponding leg on the 
opposite side, but the metatarsus and tarsus will be very diminutive; should the excision be 
made near the anterior extremity of the tibia, then the size of the coxa, femur, and genual 
joint will be normal, but that of the tibia, metatarsus, and tarsus will be very abnormal. These 
curious results plainly demonstrate, that not only reproduced limbs in their totality, but that 
particular joints also, are limited in their dimensions by the capacity of the undetached portion 
of the mutilated part in which they are developed, and that restored legs and palpi are never 
symmetrical except when developed in the undetached coxa and axillary joint respectively. 
At the penultimate moult of male spiders the digital joints of the palpi become very 
tumid, in much the greater number of species, by a sudden and rapid advance towards 
development in the sexual organs, and should these parts be detached during the interval 
which elapses between that and the succeeding moult, though the palpi, indicating by their 
organization that the animal has arrived at maturity, may be reproduced, yet the sexual organs 
are always absent; but when palpi, which had been amputated before the penultimate moult, 
are reproduced, the sexual organs, perfect in structure, are reproduced also. 
If a leg of an immature Tegenaria civilis be detached at the coxa four or even six times 
consecutively, it may be restored at each succeeding moult the spider undergoes, and this 
frequent renewal of the same part seems to warrant the conclusion that a reproduction of the 
limbs of the Araneidea generally, irrespective of mutilation, actually occurs whenever a change 
of integument takes place. 
Sometimes the stump only of a partially amputated leg is produced at the succeeding 
moult, especially when the injury has been inflicted but a short time previously to the change 
of integument, and as the formative process in this case must have made considerable progress 
before the excision of the part was effected, there is nothing extraordinary in the result; but 
it is deserving of notice that a similar consequence occasionally ensues when the partial 
amputation of a leg takes place very soon after a change of integument, before the formative 
process can be supposed to have commenced. 1 2 
Little appears to have been done for the purpose of determining the longevity of spiders 
with some approach to accuracy; that of many species evidently does not exceed the brief 
space of twelve months; others enjoy a more prolonged term of existence; and the life of 
Tegenaria civilis and Segestria senoculata has been ascertained to extend through a period of 
four years. 3 
Anomalies in structure may sometimes be observed among spiders, especially as regards 
the number and size of the eyes, but they seem scarcely to have engaged the attention of 
1 ‘Annals and Magazine of Natural History/ second series, vol. i, pp. 176, 177. 
2 Ibid., i, p. 178. 
