This third rearirit; laethod wr^.s first used at ITiclcford experi- 

 ment station in Rhode Island, U.S.A. I shall neb here give the 

 historical development of the question in iliaeric "i, i.e., a si^rvey 

 of the imny experiments with reorint^ of lobster Thich have been made, 

 as none of the used jaethods, mth exception of t.iis last one, has 

 been effecbiveo The method was invented 'by 'Dr^ A, D. ..lead (BrOTm 

 University, Providence, RbI»)« In 1900 Dr» Mead discovered that n 

 constant movement of the v/ater in the joxes where the lobster-larvae 

 vrere reared, had a t;ood effect on their development, as the percent- 

 age which reached the 4th stage, xms corsiderrbly higher than if the 

 young vrere reared in boxes witliout such movement. At the beginning 

 the water was put into moveruent by means of an ours Tliis experiment 

 gave good results, and in 1901 an apparatus was built in which the 

 Yiater in the rearing b,-;::es ivas put into movement by means of a pro- 

 peller, which again 'was driven by r mot ore The apparatus was gradually 

 improved, and as far. as one can judge from the descriptions, it had 

 already attained its present form in 1903.- From th'j year mentioned 

 there is a c' escription of the apparatus by Mea.d and 'Williams , and in 

 1906, E» Y'f. Barnes gave a full flescription with several pictures of 

 the same. Besides referring to these descriptions, I shall here give 

 a description of the apparatus used by mej this is built after the 

 same principle as the American; they differ.^ hovrever , i;omewhat in a 

 feviT respects. 



The v;hole apparatus used for the rearing boxes cr rather the 

 rearing bags is exclusively made of square planks (4 x 4 or 4 x 5 

 inches), which are put together by means of screv/s, and v/hich easily 

 can be trken apart and stored. The size of the apparatus depends, of 

 course, on the nvinber of rearing bags and on the povrer of the motor 

 or steam enginec As ray purpose was to try the r.nparatus \mder ovr 

 conditions, v/hich differ very much from the j"imerican, our apparatus 

 was made much smaller than the Americano The v/hole apparatus is only 

 28 feet 3 inches long and 13 feet wide and }ias a capacity of four 

 rearing bags, which are about 5 feet vade on all sides and 4 feet 

 deep. It is,, of course rather difficult to describe the apparatus 

 in detail, but by means of the pictures given, I hope the reader will 

 be able to understand its main features. ITith regard to the size of 

 the different parts, -f the apparatus, I refer to pl» IX; with regard 

 to the construction as a v/hole, I refer to pi. r/-DC. 



(The next pageS' give a very detailed description of the 

 apparatus . )• 



(p. 121) llith regard to the rearing bags I v.-ant to emphasize 

 that the construction of these differ essentially from the A-merican 

 oneso According tc my experie::ce as to the great importance of a 



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