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problems that present themselves to his mind, but by free 
interchange of views with others much may be learned and 
much accomplished. In this connection too much cannot 
be said in favour of properly constituted local societies; they 
afford opportunities of bringing together multitudes of honest, 
though it may be humble workers, the result of whose work 
would otherwise be lost. They can take up the working 
out of many matters, possibly minor matters in themselves, 
but which collectively are of the utmost importance; and 
they can induce among their members that spirit of systematic 
procedure that is essential to trustworthy results, and which 
fits them for taking up more advanced work should oppor- 
tunity arise. The banding together of local societies under 
the auspices of such institutions as the recently started 
South-eastern Union of Scientific Societies, and kindred 
institutions of longer standing, are further signs of the 
progress that has been made in this direction. 
Expeditions for the exploration of little-known parts of 
the world, such as that undertaken by the Government in 
sending out a biological staff on board the “ Challenger” in 
1872, and by numerous private individuals at no small 
amount of expense and hardship to those concerned, have 
produced a vast amount of material, and brought to light 
many new facts. 
The establishment of technical institutions has done 
much to encourage the study of natural science, not the 
least important among them being the Marine Biological 
stations. While on this subject it is particularly gratifying 
to note that the solution of one of the most perplexing and 
difficult problems—one that naturalists have been striving 
for years, perhaps centuries, to work out—should have been 
made known during the past year. It had long been known 
that the common eel of our ponds and rivers did not breed 
in fresh water, or even become mature there. Eels were 
further known to go down the rivers to the sea, and not to 
return, but elvers, or young eels of about two inches long, to 
come up the rivers from the sea in myriads. Grassi, whose 
work has been carried out at Messina, in Sicily, has been 
able by his careful research to complete the life history of 
this interesting creature. He tells us that the eel on leaving 
the river makes its way into very deep water, where it 
undergoes great change in both appearance and structure, 
and lays its eggs in water of not less than one thousand five 
hundred feet depth. The young which issue from the eggs 
are quite unlike the eels of our rivers. After a time they 
