Invertebrate Fauna of the Baltic. 87 



3205 x 19=60,895 was therefore the number of the Copepods 

 devoured. 1 cubic centim. consequently contained 15,223 

 specimens. Counting the two ascertained numbers together 

 and dividing them by two, we obtain 14,000 specimens as the 

 average number in 1 cubic centim. of .Temom-paste. 



I did not find Temora-])SLSte in the stomach of every her- 

 ring or sprat that I opened, and in many only 1, or 0'75, or 

 0'5 cub. centim. But if we consider that those specimens 

 whose stomachs contained from 1 to 4 cubic centims. of 

 Temora-paste were taken quite at random from a great quan- 

 tity of freshly caught animals, we shall certainly not go too 

 far if we assume that every herring caught in Kiel Harbour 

 had devoured 10,000 individuals of Temora during its sojourn 

 there. Then, to the take of one day, of 3000 " wall," each of 

 80 fish, we get 3000 x 80 x 10,000 = 2400 millions of indi- 

 viduals of Temora longicornis, and to the take of three weeks 

 43,200 millions of these little crustaceans. 



That Temora longicornis existed in great abundance in 

 Kiel Harbour at the time of the productive herring-fishery, 

 was also proved by fishing with fine surface-nets. It was easy 

 to collect many thousands of these animals. In herrings which 

 had been taken near Eckernforde I also found many of them. 



For the capture of Copepoda and other small swimming- 

 animals the herring possesses an excellent arrangement — we 

 might say, a narrow-meshed lobster-pot, to which its mouth 

 forms the entrance. This pot consists of the four branchial 

 arches on each side, and of a close series of teeth on each arch. 

 In herrings 20-23 centims. in length these teeth are of the 

 following lengths : — on the first branchial arch 7-10 millims., 

 on the second 3-4 millims., on the third 2-3 millims., and on 

 the fourth 1*5-2 millims. ; and they stand so close together 

 that there are two teeth at least in a space of 1 millim. 

 As these teeth are biconvex, the passages between them are 

 much narrower than \ millim. In the neighbourhood of the 

 inner margin of each tooth, or that turned towards the cavity 

 of the mouth, there stand two rows of spines — one row on the 

 anterior, the other on the posterior surface of the tooth. These 

 spines are from 0'2-0*3 millim. from each other. As the 

 anterior row of spines stands a little nearer the inner edge of 

 the tooth than the posterior row, the anterior spines of each 

 tooth overreach the posterior spines of that preceding it. The 

 spines of neighbouring teeth also frequently push in between 

 one another. The narrow-spaced latticework which is thus 

 produced allows the passage of the water which is to flow 

 over the branchial lamella? ; but small animals (down to 0*2 

 and 0*1 millim. in diameter) which get into the mouth of the 



