ACTIVATION OF THE Ecc By BasEs 153 
time of exposure was one hour and twenty-five minutes; the 
temperature 18°C. The concentration of the bases chosen 
was that found most effective in the writer’s previous experi- 
ments on artificial parthenogenesis. The oxygen consumption 
was first measured in a neutral solution and then for the same 
eggs in the alkaline solution in which 0.3 ¢.c. N/10 of the various 
bases was added to 50 c.c. of the solution. 
This influence of the various bases upon the rate of oxida- 
tion in the eggs of purpuratus runs parallel to their relative 
efficiency in causing development in Polynoe. To induce 
artificial parthenogenesis in the eggs of Polynoe the simple 
amines were found to be most efficient, next came NH,OH and 
trimethylamine, and finally the strong bases NaOH and tetra- 
ethylammoniumhydroxide. The amines seem to hurt the eggs 
of purpuratus more than those of Polynoe. 
Incidentally it may be stated that NaHCO, does not 
accelerate the rate of oxidations in the unfertilized egg, nor 
does it cause artificial parthenogenesis. 
7. We compared next the relative effect of various concen- 
trations of NaOH and NH,OH upon the rate of oxidations in 
the unfertilized sea-urchin egg, during one hour. We will 
state only the coefficient of the rate of oxidation in the various 
solutions calling the rate in the neutral solution 1.00. 
TABLE XXVII 
| 
| COEFFICIENT OF ACCEL- 
ERATION OF OXIDA- 
a : aa or O 
$0 cc m/2 (NaCl+KCL+ ee 
CaCl) 
NaOH | BEE EI 
LOCC ee Souk oplle29 
(hn CY Carne eee ae ee 1.87 | 5.00 
DS C05 ee eee 1.74 5.94 
OMORC SG oles sts sie es © Sic ane 2.06 | 6.10 
eerie roi oxbidccitm.s'e «= 2.32 6.40 
DiC C.O sea eae Dees ae ore | 3.42 6.23 
7) fs CHESS Ga re, eG Bao ONa ee | 1.57 5.70 
Doll CxS ecto Selo eerie Y 2 Goo 6.00 
