58 



jects anti also to Ulva ; the water at that place had a depth of 

 about 5 or 6 feet, the temperature was 14°8 C. and the salinity 

 O.BSo/q (areometer 1.007). Whereas the bottoni was rather muddy 

 at the Volendammer corner , it was composed here of a mixture 

 of mud and sand. 



These two places must no doubt be considered as two of the 

 most important spawning places of the Zuiderzee herring. Pro- 

 bably there are other such places : as for example extensive 

 parts of the so-called »Knar", the shallow parts to the north of 

 Pampus, flat grounds along the coast of Overijsel, and so on. As 

 a rule these are the places where the bow-nets are used and drag- 

 net fishing is tried : the herrings taken with these apparatus (near 

 Marken, Urk, at the Knar etc.) are over-ripe and almost worthless 

 fishes which visit the shallow places towards the end of the fishing 

 of each spring there to propagate their species. 



It was on 23 May '88 that I caught the first free-swimming 

 herring-Iarva. In the table here inserted I give a list of the 

 different points where herring-larvae have been collected. 



I 



