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TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



The first of these nets is the basket net (" Korbnetz "), 

 so-called because the protective covering was originally 

 of basket work. This has now been dispensed with, and 

 a strong metal covering has been substituted. This net 

 is shown in section (fig. 10). A is a strong metal covering 



Fig. 10. 



240 mm. high, which at B is soldered to a thick metal 

 ring. C is a hollow metal cone, which is so screwed on to 

 the cover D that a ring-shaped opening is formed. The 

 diameter of the cone at this point is 40 mm. ; the diameter 

 of the outer edge of the ring-shaped opening is 48 mm. 

 The whole cover is fastened on to the metal conical cover- 

 ing b}^ means of three overfall screws, one of which is 

 represented at E. The cover D rests on a ring F which 

 is covered with fustian, and to which the net (N) itself is 

 sewn. When in use the net expands, because in the under 

 surface of the metal cone there are two small apertures of 

 a total area of 5*5 square centimetres. Through these 

 openings the water escapes, and so the expansion of the 

 net is brought about. 



The net is let overboard over the stern of the 



