ing of tho conditions v/e have to innkc investigations concerning the 

 mortality of the different stages ns the temperature of the sea v/riter 

 changes* I have not oeen able to make as accurate investigations as 

 could be desired, but as far as I can understand the first stages 

 are especially very sensitive to lov/ temperature - or to a drop in 

 teiiperature« This problen can, hov/ever, be relatively easily solved 

 at Fl/devigen, as the temperature in the rearing basin to a certain 

 extent mi;;^ht be regulated. If it should be proved that the toiuper- 

 ature plays an inportant part, so that the death rate decreases at 

 a higher teraperature, then \ic could move the v/holc rearing v/ork to 

 the basine 



The cannibalism of the lobster young lias for a lonp; time been 

 regarded as the most serious impiedincnt for an economical rearing 

 v/orke I CLO not agree here; it certainly plays a part, but I do not 

 thinlc it an essential cause of death* This year, at least, I have 

 only by exception seen that one yoiong lobster really killed another - 

 oven if thsy viore of different sizes. Experiment No* 4 shows this 

 very clearly: when the brood had entered, the 3d -^r -Ith stage, 300 

 nevfly hatched brood vrero put in, and of these 75 xrcre still alive 

 (in 2d and 3d stages) after 11 days, i.e. the result v;as not rrarse 

 than those of the other experiments* 



In addition, in 191'i I examined 50 dead young lobsters from tho 

 rearing apparatus at Korshavn} of these 10 vrere badly hurt, 17 partly 

 hurt while 23 were without visible injury; (tho examination was :.xide 

 by means of microscope). 



I'yTien only a fraction of the dead young vms hurt in such a vmy 

 thr-t \ie hught suppose the injury to be the cause of rov.tht and nt 

 the same tine the inixiry might have taken place after the young had 

 died of another cause, - tlien the cannibalism is only of rclr.tively 

 little importance^ Of the 50 young lobsters examined there was 

 only one (2d stage) vrhich had remains of young in the ventricle; the 

 other ventricles were usually empty, or partly filled with an 

 amorphous undefinable content. The brood had been fed with hard 

 boiled eggs. 



Before I finish the rep-rt on the v/ork of this suirxier, I also 

 have to mention tho storm on August 3. In spite of the f?.ct that 

 the rearing station is located in a well protected creek, the spray 

 flev/ over the station for several hours; several "windows" were 

 smashed into the boxes, and the sea v/ent oompletely over tho rearing 

 bo:ces. I- number of the moorings were broken, and the menvere so ousy 

 in trying to keep tho station in place that there v/as no time to care 

 for the young. The storm, vj-as followed by a violent decrease in 

 temperature - dcvm to 11*5'-' C. (maybe Icvrer); only gradually it 

 increased to a normal suxmer temperature again. 



41 



