The tine also, within v/hich the 4th stp.j,;e was reached, -vms in- 

 variably shorter in 3.920 than in 1919, ieOo 11 - 13 days as against 

 15 - 19. In 1919 at a temperature of 17'^7, it took 15 days vmile 

 in 1920, T;hen the temperature Y/as lorrer, only 12 days elapsed before 

 this stage vras attained, 



■ From. the above it virill be clear tiiat the optinum living require- 

 riwnts of the larvae are being approaclied inore and iaore« 



Of all the larvae placed in the rearing tanks, 4,2 per cent 

 could be released into open rmter as j'^oung lobsters of tlie -1-th sto.ge. 

 Undoubtedly this percentage is already a good deal higher than that 

 which would have been e stablished under natural conditions « 



Taking into consideration only the s:nall tanks (and these only 

 could be given the necessary care and will therefore be used pre- 

 ferentially in the future) the average percent'^ge is already much 

 higher, naiuely 8.: 3 per cent. 



But a very snail part of the hatching larvae can be used, once 

 the tanks are stocked, which riust be done in one day, the larvae 

 emerging aftemvrrds nust be releasodo These are howe~.'"er not necess- 

 arily lost, they r.iay continue to develop naturally c: 



The tests have taught us that it is always possible to bring 

 lr>rvae into the desired 4th stage* The problen now is to discover 

 the circumstances under v/hich the percentage can be raised to the 

 highest point.-, Details of the iiethod er.iployed as well as the 

 installation used will have to be iinproved-upon. Already in 1920 

 r.any errors and short coviings were corrected. 



In 1919, when only tno two large tanks Y/ore available, it 

 proved inpossible to stock these r.dthin a short tine with sufficient 

 Quantities of larvae* Durin,;; the first days not nore than 100 - 250 

 larvae vrould usually hatch. The seed lobsters in store raiounted to 

 about 100. Even at the height of the season not nore tV.an 1500 

 larvae hatched out daily. Since the tanks could easily hold 10,000 

 larvae the seed lobsters had to be kept in the tanks fron 7 to 10 

 dr.ys to get a fair supply so that t he larvae present differed frcia 

 7 to 10 days in age» The older larvae were usually in the second 

 stage by the tine the youngest ones emerged fron the eggs. It v/ill 

 be plain that the sinultaneous presence of stronger and weaker 

 larvae considerably increased carjiiibalisne The worst was that the 

 cause of these losses cauld not be avoided, this could only have 

 been done by the acquisition of 800 or nore seed lobsters, an 

 inpossibility as far as vre v/ere concerned. 



To overcone this durin, the succeeding year it v;as decided in 

 1920 to construct tanks of only l/s of the previous volume.. As a 

 consequence the difficulty war. indeed eliiainated. 



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