578 Charles Zeleny 
TABLE 6 
Amblystoma jeffersonianum. Nos. 2032-2076. First regeneration. Younger individuals. Regener- 
ation period = 24 days (February 17 to March 13, 1907). Age at time of operation = 28 days 
| | SPECIFIC | SPECIFIC 
CATA- | PART OF TAIL TOTAL LENGTH OF | LENGTH OF | | 
LOGUE REMOVED LENGTH OF | REMOVED |REGENERATED| “MOUNT OF | RATE O8 
NUMBER | (APPROX.) ANIMAL TAIL TAIL Miaeenise sea co 
TION TION 
2033 whole | 22.0 8.4 9.5 | Eig SA Oem 
2039 whole | 20.0 8.1 8.1 | 1.00 ©.042 
2043 whole 24.0 9.8 8.1 | 0.83 0.035 
2046 whole | 23.0 9.1 10.0 I.10 0.046 
2049 whole 25.0 10.1 rey) | 1.05 0.044 
2053 whole 21.5 8.4 10.6) 1.26 0.052 
2058 whole | 21.5 8.5 9.2 1.08 0.045 
2061 whole 22.0 8.5 8.6 | 1.01 0.042 
2072 whole 24.0 9-4 ee Sa, 1.00 0.042 
2076 whole 23.0 9.1 9-5 1.04 0.044 
SYUMERED cd bdasnoooeonos 22.6 8.94 Os | 1.05 0.0439 
(cag. | 
2054 half 19.0 6.7 rye 1:15) 4| seqe 
Tables 6 to 11. The eggs were collected on the morning of January 20, 1907, and were probably 
laid during the previous night, all being in early cleavage stages at the time of collection. Nos. 2000: 
to 2014 are exceptions, being collected on January 8. The specific amount of regeneration is the 
amount per unit of removed tail. ‘The final measurements made on June 20 are from the animals 
as killed in Gilson’s fluid and preserved in 85 per cent alcohol. In Table 10 “‘no” regeneration means. 
less than 2 mm. in, Table 11 it means less than 1 mm. 
