194 



THE SMALL GAME OF THE SEA 



occur practically all the year round, and are most abundant in 

 spring and summer just as most of the young fishes put in an 



appearance. One young hake, 6 millimetres long [ ] contained 



six copepod larvae — this gives some idea of their size — and 

 Dr. Lebour has detected eggs probably belonging to these 

 copepods inside young whiting, mackerel, lemon soles, and 

 brill ! The eggs are 0-06 millimetre — say one four-hundredth of 

 an inch in diameter. 



After the copepods, in order of popularity among baby fishes, 

 come the Cladocera or ' water fleas '. These are depicted in 

 Fig. 25. They have two shells, a large pair of antennae. which 

 they use as oars, and one large eye. They are only common off 

 Plymouth in the summer, and are then eagerly taken by the 

 very youngest fish. 



Fig. 25.— cladocera or Water Fleas '- 



a. Podon, 1 mm. b. Evadne 0-9 mm. 



Drawn by Dr. M. V. Lebour. These water fleas are eaten freely by the newly 

 hatched turbot, soles, megrim, plaice, brill, and lemon soles. 



Third in importance come the young barnacles. These are 

 not, like their parents, attached to rocks or to the bottom, but 

 swim about freely. Plate XIX shows them at two different 

 stages of their ' free-swimming ' life. The barnacle really lives 

 in the tidal area near high-water mark. It has found its way — 

 thanks to its larvae — down stream of the currents to the 

 Murman coast ; but is never found in Spitsbergen. Yet it can 

 survive after it has been encased in ice for a considerable time. 

 The larvae appear off Plymouth in numbers in winter and early 

 spring ; and again in July and August. 



The mollusca also feed young fish in their very earliest stages, 



1 Copepods and water fleas both belong to the order ' Entomostraea ' or 

 crnstaeeans with shells cut in two. Nearly all of them are one-eyed, and Calanus 

 tinmarohicus used to be called Monoculus linmarchiiiis in 1705. 



