232 Mr. J. Blackwall on the Structure, Functions 



had the anterior leg on the right side and the third leg on the left 

 side detached at the coxa, the terminal joint of the superior and in- 

 ferior spinners on the right side being amputated at the same time. 

 This spider moulted on the 27th of September, when the detached 

 parts, of a smaller size than the corresponding parts on the opposite 

 side, but perfect in structure, were reproduced. On the 6th of No- 

 vember it changed its integument a second time, and on the 16th of 

 June 1 839 a third time, when it arrived at maturity. The reproduced 

 parts advanced perceptibly in growth at each successive moult, but 

 did not ultimately acquire their lull dimensions. 

 • 3. A young male Tegenaria civilis had the digital joint of the left 

 palpus, which was very tumid, detached on the 6th of October 1838. 

 It moulted on the 17th of June 1839 and reproduced the left palpus, 

 which, though small, had the radial joint provided with the apophy- 

 sis characteristic of a state of maturity in this species. The sexual 

 organs, however, were altogether wanting, and the digital joint was 

 slightly modified in size and form by this circumstance. It is scarcely 

 necessary to remark that the sexual organs connected with the right 

 palpus were fully developed. 



4. The digital joint of the left palpus of a young female Segestria 

 senoculaia was amputated on the 18th of May 1839. This spider 

 cast its integument on the 8th of July, the left palpus, of a small size, 

 being reproduced. It moulted again on the 28*h of June 1 810, when 

 the reproduced palpus had its dimensions enlarged and the spider 

 arrived at maturity. On the 12th of December 1842 it died, having 

 existed neariy three years and a half in captivity. 



5. On the 8th of June 1839 a young female Agelena lahyrinthica 

 had the terminal joint of each superior spinner amputated. Bring- 

 ing the extremities of the tarsi of the posterior legs to the mouth, it 

 moistened them with saliva, and repeatedly applied them to the mu- 

 tilated parts. On the 21st of the same month it moulted, and the 

 superior spinners, of a small size, were reproduced. It moulted 

 again on the 12th of the ensuing July, when the reproduced spin- 

 ners were increased in size, and it arrived at maturity. 



6. A young male Textrix lycosina had the terminal joint of each 

 superior spinner amputated, and the third leg on the right side de- 

 tached at the coxa, on the 25th of July 1839. This spider cast its 

 integument on the 6th of the ensuing August, when the stumps only 

 of the mutilated parts were produced. On the 2nd of December, in 

 the same year, it moulted again ; the superior spinners and third 

 leg on the right side, of a small size, were then reproduced, and it 

 arrived at maturity. 



7. The left palpus of a young male Tegenaria civilis, the digital 

 joint of which was very tumid, was amputated at the axillary joint 

 on the l.")th of January 1840. On the 22nd of June, in the same 

 year, it moulted, reproducing the left palpus, which was of small di- 

 mensions. The radial joint was provided with an apophysis, indica- 

 ting the mature state of the spider, but the digital joint was some- 

 what modified in size and form, and the sexual organs were not repro- 

 duced. 



