Libe rntion of the larvao 



The 2,708 larvae v/hich foriied groups 3, 4, 5 r.nd 6 hove been 

 liberated in the sea August 15, in front of Cap-Rouge," Grande Rivere 

 in the saiae region where the biological station places its traps. 

 Before their liberation, vre have accliinated these larvae to the 

 temperature of the sea vrater, then several degrees lower than that 

 of our rearing basins* If we have terninated the rearing so abruptly, 

 it is that at this date that hatching vms end^d and it should have 

 been very costly to keep the rearing station in operation during the 

 time that it should have taken the last larvae to reach the fourth 

 stage. 



Moulting 



We have attentively observed the grov>rbh of the larvae in the 

 rearing basins, particularly dui»ing their sheddings. Enov/ing to 

 v/hich group each larva belonged, v;e were able some days later to fix 

 its age* It is thus that vre have found that there must be eight days 

 for the larva to pass flron stage one to stage tvro, five days from 

 stage tvro to stage three, and si:: days from stage three to stage fotir, 

 viz. in all nineteen days. But that period vfill in reality be slight- 

 ly shorter, as for zero tine have we considered no exact date, but a 

 period of two to three days. Thus the larvae of the first group had 

 hatched betvreen July 14 and 16 and we have considered all' of 'them as 

 hatched the 14th. 



Feeding the larvae in captivity 



He have fed the larvae v;ith a beef liver soup, prepared by grind- 

 ing the frozen liver. This liver vras first passed through a meat 

 grinder and then through a mixer (Waring blender) after which it had 

 the appearance of a real emulsion. Every two hours one gave to each 

 of the groups about 50 grams of this emulsion. 



During the four and a half weeks of operation we have fed 261 

 livres (I30e5 kilograms) of liver. 



Pro'bable cause s of failiore 



Rearing conducted on a larger scale has presented new difficult- 

 ies. The first cause of failure showed in the hatchingo Transporta- 

 tion and manipulation, although fulfilled in the best possible 

 conditions, seems to have caused the heavy mortality recorded among 

 the females and particularly among the eggs. In the first place, vre 

 have credited to the existence of different environmental conditionsi 

 however v/e have discovered the deviation of temperatijre and' salinity 

 so minute in proportion to that of the reservoir virc.ter, that v>re do 

 not believe that T;e ought' to take it into accoxuit. 



Observation may give us further information on the causes of 

 failure. In particular, we have noticed that the majority of the 



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