.■•-■: (p. 28)- ■ ■ 



The important facts Virhich are revealed v/ith the study of these 

 Tables are the folloviring: 



♦ 



, • 1) The percentage of survival, cither in the oval tan]:s or in 

 the "Boothbay Harbor" type tanlcs, is much greater among the Inter 

 groups than among the earlier. It goes vdthout saying that the 

 personnel, in gradually ft .:ni liar i zing themselves with the numerous 

 secrets of this delicate rearing, has improved either the methods of 

 feeding or those of the acclimatization of the larvae. J'loreover, we 

 are of the opinion that the later reckonings of young larvae have 

 been more judicious than, the earlier in that sense that the weakened 

 individuals vdth little life have been eliminated at the time of the 

 earlj'' census thrt had not been made for the first groups. 



2) Each group of larvae<used in rearing must be homogeneous, 

 that is to say, that this group ought to be composed of individuals 

 of the sane agec This statement shoi'/s itself naturally in comparing 

 the survival resul-^s for the groups of the two t;-r;e3 of tanks. 



3) The conducting of a rearing of many thousands of lai-vae in 

 one tank may appear hazardous; if an accident occurs, it involves 

 the decth of many thotisands of larvs>.e» iJoreover if the sioaller 

 groups appear to rom.edy this eventuality, on the contrary, they 

 multiply the smveillcncc anr the chances of accidents. 



Larv ae reaching the fourthstage: 



Of the 177 .,276 young larvae used in rearing, 8,163 have reached 

 the 4th stage. The average percentage s\irvival to the third shedding 

 in the course -.f the season is 4.61^. This percentage is 4.3/^ for 

 the rearing conducted in the oval tanlcs and Mai""' in "the "Boothbay 

 Harbor" type tanks. This average yield is inferior to that of the 

 Boothbay Harbor Station. At the time of a visit in June, 1946 to that 

 Station, one informed us that the average survival to the 4th stage 

 vms estimr.ted at 20 or 25/t. It is a question of a r .ugh evaluation 

 not admitting deduction. The yield of 23.2/b in t?ic group 9 com.pares 

 to that of Boothbay Hnrbor. The results of this rearing are shovm in 

 Table XIII and in Table XV nre reported the average yields obtained 

 for each group of larvae used in rearing. 



The majority of the larvae reaching the 4th -stage have been 

 liberated in the sea, generally opposite Gape Rouge at Grand Riviere, 

 and at depths of 1 to 3 fathoms. In advance of their liberation, the 

 individuals \rere gradually acclimated to the tem-perature of the sea 

 water. The larvae ha-ve been liberated in clear weather and crlm ser. 

 Immediately after their liberation, the larvae directed themselves 

 toTrards the bottom; they disappeared from the surface of the sea 

 after about ten minutes. 



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