-------------+----------------------------------------------- |Duration of life of the eggs of _S. purpuratus_ -------------+-----------------------+----------------------- _Temperature_| _Unfertilized_ | _Fertilized_ -------------+-----------------------+----------------------- °C. | _Minutes_ | _Minutes_ | | 32 | { > 1-1/6 | 1-1/2 | { < 2 | | | 31 | | { > 2-1/4 | | { < 3 | | 30 | { > 3 | { > 4 | { < 5 | { < 5 | | 29 | | { > 6 | | { < 7 | | 28 | { > 8 | { > 11 | { < 10 | { < 13 | | 27 | about 18 | { > 20 | | { < 22 | | 26 | { > 35 | { > 35 | { < 40 | { < 40 | | 25 | | { > 76 | | { < 81 | | 24 | { > 168 | { > 192 | { < 200 | { < 209 | | | | _Hours_ | | 22 | | 10-1/5 | | 21 | | 24 | | 20 | | 72 -------------+-----------------------+----------------------- These observations show a very high temperature coefficient near the upper temperature limit, and this may account at least partly for the fact that in tropical seas the pelagic fauna is so much more limited than in polar seas.[308] It is quite probable that the high temperature coefficients at the utmost limits are only an expression of the coagulation time of certain proteins.