JENKINS AND Carson, Nervous Impulse in Worms. 267 
TABLE II. 
Summary of experiments on Aulastomum lacustre. 
Postero-anterior rate. 
No. of No. of records Length of } ; 
experiment Distal Proximal cord in cm. Rate in em.; 
, ae i ah 10.50 42.0 
2 23 23 10.25 59.4 
3 i + 10.50 39.9 
4 28 27 10.50 57-7 
5 15 18 10.25 48.2 
6 8 9 10.50 45.1 
7 29 25 11.00 47.0 
8 18 21 10.50 87-1 
9 II 15 II.00 572 
10 12 6 10.50 80.8 
Il 26 16 II.00 91.3 
12 16 19 11.00 Bye 
13 18 26 10.50 52.5 
Mean rate: 56cm. per sec. 
Standard deviation: 16. 
Coefficient of variability: ,28. 
Cirratulus sp. 
This species is very common at Pacific Grove where it is 
found under the rocks and in their crevices throughout the lit- 
toral zone. It reaches a length of fifteen to twenty cm. The 
posterior portion of the body is very slender and fragile and too 
DIDIPIPPPPPPPLPLIIIIPIPUIPPIPLIISPPLPPIPIPPLSPSPPSSPLPPP PPP IIPLPP PLP PPS IIIS PLP IP LL SL LI 
Fig. 3. Cirratulus sp. Postero-anterior. Length of nerve cord between distal 
and proximal electrodes: 9 cm. Rate: r00cm. persec. Time: 50 d.v. 
per sec. 
feeble to raise the lever of the apparatus, consequently the an- 
tero-posterior rate was not determined. The head end, how- 
