and (Economy of the Araneidea. 231 



same month, it moulted again on the 17th of August, the 4th of 

 September, and the 26th of September, in the same year; and on 

 the 26th of January, the 9tli of April, the 24th of May, the 21st 

 of June, and the 5th of August in 1843, when it arrived at maturity, 

 having changed its integument nine times. 



A male Tegenaria civilis, extricated from the egg on the 27th 

 of June 1842, also moulted nine times, casting its skin in the cocoon 

 on the 10th of the following July ; on the 21st of the same month 

 it abandoned the cocoon, moulting again on the 13th of August, the 

 10th of September, and the 13th of October, in the same year; and 

 on the 1st of February, the 25th of April, the 17th of June, the 13th 

 of July, and the 17th of October in 1843, when its development 

 was complete. 



Modifications of food and temperature exercise a decided influence 

 upon the moulting of spiders. A young female Tegenaria civilis 

 disengaged from the egg on the 24th of July 1842, on the 2nd of 

 the following August moulted in the cocoon, which it quitted on the 

 12th of the same month, casting its skin again on the 29th of Au- 

 gust, and the 10th of October, in the same year ; being scantily sup- 

 plied with nutriment, it increased very little in size, and died on the 

 4th of July 1843, having changed its integument three times only. 

 Another female of the same species, which was extricated from the 

 egg on the same day as the foregoing individual, and was well-fed, on 

 the 13th of July 1843 had moulted seven times. It is apparent also 

 from the particulars already stated, that the intervals between conse- 

 cutive moults are much shorter when the temperature of the atmo- 

 sphere is high than when it is low. 



Immature spiders infested by the larva o^ Polysphincta carbonaria^ 

 an insect belonging to the family Ichneumonidce, which feeds upon 

 their fluids, never change their integument*. 



Like certain animals of the class Crustacea^ spiders possess the 

 property of reproducing such limbs as have been detached or muti- 

 lated, and this curious physiological phaenomenon is intimately con- 

 nected with the renovation of the integument, as it is observed to 

 take place at the time of moulting only. Experiments illustrative of 

 this interesting subject have been multiplied to a very great extent ; 

 in introducing some of them to notice, such have been selected, as 

 from the novel and important conclusions deducible from them are 

 best deserving of attention. 



1 . A young male Textrix lycosina had half of the terminal joint 

 of each superior spinner amputated, and the posterior leg on the 

 right side detached at the coxa, on the 3rd of August 1838. It 

 moulted on the 10th of September, reproducing the detached parts, 

 which were small but perfect in structure. On the 23rd of Febru- 

 ary 1839 it moulted again and became adult; at the same time a 

 sensible increase took place in the bulk of the reproduced parts, 

 which, nevertheless, were still defective in point of size. 



2. On the 23rd of August 1838 a young female Tegenaria civilis 



* Annals and Magazine of Natural History, vol. xl. p. 1-4. 



