THE EEL FAMILY. 



majority of the adult eels leave the streams and rivers and 



migrate to the sea. Some of the eels, however, remain in fresh 



water during the winter. That this migration to the sea is for 



the purpose of spawning seems to be proved by the fact that 



about the end of spring and beginning of summer, immense 



numbers of young eels enter the fresh water streams from the 



sea. While most authorities are agreed that the eels spawn 



only in salt water, some are of the opinion that they also spawn 



in fresh water. Roosevelt maintained that eels were hatched 



in fresh water in his trout-ponds in Great South Bay, Long 



Island. Sawyer also considered that eels do not all return 



to salt water to spawn, but spawn wherever they find suitable 



places in ponds and rivers. In this connection Benecke says 



that 'eels planted in land-locked ponds increase in size, but 



never increase in numbers. In lakes which formerly contained 



eels, but which by the erection of impassable weirs, have been 



cut off from the sea, the supply has diminished, and after a 



time only scattered individuals, old and of great size, are taken 



in them. If an instance of the reproduction of the eel in fresh 



water could be found, occurrences such as these would be 



inexplicable.' At the meeting of the Scottish Microscopical 



Society on the 16th of February, 1894, Mr George Sandeman 



called attention to some remarkable eels from a warm and 



stagnant loch on the Isle of May, which has no communication 



with the sea. He remarked that it was not known how long 



ago the eels were placed in the loch, but it did not appear to 



have been within the memory of man. They are not known to 



breed, their ovaries and testes being somewhat atrophied, 



though still apparently functional. In the specimens examined 



(at St Andrews Laboratory), atrophy is also marked in the 



muscles, liver and spleen. The ovaries and ova are very small, 



fatty, and the nuclei of the ova obscured. In appearance these 



eels are singularly bony. The specimens were all about 2G 



inches long, but weighed only one-half the normal weight. 



Perhaps the most interesting feature about them was their 



eyes, which in some examples were eight times larger than 



normal. The cornea is opaque, and attacked with gregarines 



and other organisms. These very remarkable abnormalities 



