604 Sergius Morgulis 
On the 16th day the rate of regeneration varies within still wider 
limits, but those with eight regenerated segments are quite typical. 
The considerable degree of variation in the number of regen- 
erated segments at the period of 12 to 20 days after the operation 
is due to the fact that some of the worms are slower in starting 
to regenerate and which also linger behind the rest of the worms 
in the process. 
The records of the number of new segments found at the end 
of every four days, likewise the average number of segments for 
each corresponding period, are given in Table III 
TABLE III 
AVERAGE |AVERAGE 
| NO. OF | LENGTH 
DATE OF 
NO. OF REGENERATED SEGMENTS NEW | OF RE- 
EXAMINATION | 5 
| SEG- | GEN. 
| MENTS | TAILS 
am) | | mm, 
Ata C Mee AE Sat Seo. Bahccael 5) Sy] wees Oi er Nes ose | 523 ea 
7p) a Rb tao Oetier 4 Goebel) 77] eB al eRe Saal eRe aay | 6.6 0.69 
#45) «3 OG OS ERI Z| 5) 6) 6) 7) 7) 8.1 97. 9) ol o [pte) (7 aealeeomee 
Hise cuaoac cone een, eh eP ltmthls eh |) G4) 8G) i, Sol Geller ai 8.1 0.96 
| | | | | | 
SEPE Oia aatiosttyee'e ss Sal Oa OPW a B Si 2911/19) |) 90] g || 10" Yea 1.00 
Rs ee teen 
From this Table III it will be seen that after a period of rapid 
formation of new segments (the first four days) the number of 
segments regenerating for a certain period of time begins to 
decrease and continues: to do so steadily. . This condition is 
illustrated in the diagram, Fig. 3, where the horizontal line is 
divided into equal portions, each corresponding to a period of 
four days, and the vertical columns correspond to the average 
number of segments regenerated in course of those periods, as 
shown in Table III. 
Of the worms from which one-third of the body had been 
removed, only 14 per cent proliferated new tissue at the end of 
two days; for the first four days from 2 to 3 new segments have 
regenerated, as seen from Table IV. 
