pods, and because most of us are familiar with them from our early 

 dawning of consciousness, they tend to overshadow their marine 

 relatives, such as the crustaceans and copepods. All of us are ac- 

 quainted with crabs, lobsters, and shrimps, but to most of us the 

 copepods are as unfamiliar as Chinese script; yet our harvests of the 

 sea, by which so much of our civilization is sustained, depend on 

 copepods. These seemingly insignificant and unfamiliar crustaceans 

 are one of the chief mainstays in the total economy of that two 

 thirds of the world's surface covered with salt water. 



Just as an understanding of the copepods eludes most of us, 

 their essential value in the economy of the sea eluded marine bio- 

 logists until fairly recently. Although fishes have been known and 

 exploited for millennia, the basic principles of their existence - in 

 this instance their food - were wrapped in mystery until the nine- 

 teenth century. Spectacular discoveries in many areas of marine 

 biology have been made over the years, but always they have come 

 about slowly, and usually through the persistent efforts of obscure 

 workers. An attempt to follow the history of marine biology is like 

 a journey through a labyrinth, the most important signposts of 

 which are obscured by moss. 



Consider, for instance, one of the supreme examples of this state 

 of affairs. Paradoxically it concerns a fish most of us think of as a 

 fresh- water fish, although it spends the first part of its life in the 



The crustaceans, having skeletons on the 

 outside of their bodies, include lobsters, 

 shrimps, and crabs. Shown here is the larva 

 of a velvet swimming crab (magnified many 

 times). At this stage in its life cycle it 

 forms one of the many varieties of plankton, 

 the basic food source in the sea. 



77 



