118 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



II. 



According to this observer, if a spider (Trochosa) lose a foot while 

 very young, it will be restored at the last moult with such perfection that 

 it cannot be distinguished from the others. If the member be 

 lost at a more advanced age, after the eighth or ninth moult, it 

 will be renewed imperfectly, and although the number of joints 

 will be complete the restored limb can easily be distinguished. This is 

 illustrated in Fig. 79, a drawing of the Huntsman spider, Heteropota ven- 

 atoria, a specimen which I obtained in Florida, one of whose hind legs 

 is seen to be shorter than the other, a moulting defect. In such cases 

 the defective limb is usually not only shorter but smaller, of paler color 

 and with less numerous hairs. Such a fact indicates that Nature has 

 provided a certain amount of vital force and substance, for the exigen- 

 cies of a spider's life, which cannot wholly answer the draughts made by 

 the regeneration of adult limbs, although responding invariably to the 



Flu. 79. Huntsman spider with one leg (4) shortened in moulting. 



recuperative demands of early life. I have already referred to another 

 case in point, a large tarantula, when speaking of the dangers of the 

 moulting period. 1 



As to the relative perfection with which lost limbs are reproduced, 



Blackwall considered it to be in inverse ratio to the extent of injury. 



Thus he found that palps and legs detached at the coxa were 



feet usua iiy reproduced symmetrical but diminutive ; while those 



j on amputated at the articulation of the digital with the radial joint, 



and near the middle of the tibia or of the metatarsus, \\crc 



always much larger and unsymmetrical when restored. In point of fact, 



therefore, the development of the new limb depends upon the vital capacity 



of the undetached part. Thus, if a leg be amputated near the middle of 



1 See Chapter V., above. 



