38 TIME. 



and then the best diet is the lean of raw meat, 

 cat into minute fragments ; but it should be very 

 sparingly done, and the rejected atoms carefully 

 removed, lest putrefaction set in and spoil the 

 whole. 



INSTRUCTIONS FOR COLLECTING. 



Time. — What is commonly called low-water — 

 that is, the time when the ebbing-tide recedes to 

 the utmost point — is the period to be chosen for 

 shore-collecting, as comparatively few marine ani- 

 mals or plants habitually live in situations where 

 they are long exposed to the air and sun. But the 

 lower the level, the more rich becomes the harvest ; 

 and hence the time of spring- tide is the most pro- 

 ductive, when the recess of the tide is the greatest. 

 Spring-tides occur twice every month, viz. about 

 the time of new and full moon ; the very best tides 

 of all are those of the second day after the change 

 of the moon ; but for two days before and two days 

 after that, they recede very far ; so that we may 

 consider those weeks which commence two days 

 before the change of moon and end five days after 

 it, as good collecting periods, while the alternate 

 weeks are nearly useless. The full-moon tides are 

 generally greater than the new-moon ; and those 

 about the time of the equinoxes, or the spring-tides 

 of March and April, and of September and October, 

 are the best of the whole year. Prevailing winds, 

 however, exercise some influence on the amount of 

 recess of the tide. 



The time of lowest water on any particular day 

 can be readily ascertained from local tide-tables ; 



