single residue (cast off s?icll)o On t?it other hnnd, tl.e f i Icnent ous 

 elongated antennae of the body hr.ve bucome visible. The body length 

 is c.bout 16 inr.ii( Directly after the fourth moult the younp; lolstcrs 

 still s^Tin about for a short time, about bv/o to three days, then 

 hoiTever they seek the bottom and hide theiiselves as vrell as possible 

 under stones v;hich they only seldom leave in order to ?iake some short 

 sv/iraming movements* The fourt?i sta're is according to Appcll/f 23 to 

 28 days oldj in Helgoland v;e observed, in perhaps a dozen cases, 

 t?iat it vras 17 days (25,8 to llo9), in somewhat later season hovrever 

 (it T/as ) also 25 days oldc 



Accordingly it follorred from these observations on the speed 

 vfith Tfhich the first sheddings followed them-selves thn.t tiie plajiktonic 

 life of the larvae lasted at least 19 to 22 days — thus around three 

 vreeks ~ ond at most four to :?ive Treekso Since this period vhich is 

 by far the most dangerous in the life of the lobster, ' n Trhich the 

 greatest reduction of stock occurs,, so it is of great; importance that 

 it most quickly terjiinates; and for this, as one sees it, a high as 

 possible ivater temperature is necessaryo It is therefore 3.iot T;ithout 

 meaning that at Helgoland where the average teiTperatv.re of the sea 

 water reaches its ma::imium in the second half of August (at 16.8 

 degrees Cc) most of the lobsters rre born in August and complete their 

 planktonic stages during; this months 



Moreover, it deserves to be esr.phasized that the grectest obstacle 

 to the successful rearing of young lobsters is not the often unpleas- 

 ant result of the shedding process but instead the cannibalistic 

 tendency of the larvae to eat up each other reciprocally* All attempts 

 to check this tendency have been futileo P'or if .one offers the larvae 

 also copious quantities of finely ground crab flesh, then to be sure 

 they eat of it, but do not yet cease their habit of assailing their 

 comrades c Not merely older larvae are dangerous to the younger, but 

 also equal-aged ones fall upon each other and Icnow to find with skill 

 the susceptible place— the connection between carapace and taill 

 Appell;{f obsei-ved that 20 to 30 fourth stage lobsters destroyed daily 

 50 to 80 first stage larvae and left hardly three to fovr of them 

 remaining. Especially the fourth stage turned out to be particularly 

 prcdaceousi The anii.xils, usur.lly for the first time, use the claws 

 in this stage for attack while they used only the mouth parts in the 

 earlier stages o The English scientist Cunningham expressed the 

 opinion that the lobster larvae take principally no living food, 

 neither in the free state nor in captivity, and that in the latter 

 case it may be a certain sign tliat the larvae may be healthy no 

 longer, if they become concerned with each other^ Appell/f, to 

 whom we must agree according to our experience, contos^-d this quite 

 decidedly. He has often seen that one larva swam .about with another 

 one half consumed, but still living? now they attack each other from 

 the front, nov/ from the rear, now diagonally; and also occasionally, 

 if the attacked (ones) are successful in freeing themselves, then 

 they are however mostly but so daraiged that they subsequently perish. 

 It may be observed that with the rearing in glass vessels the victims 

 of cannibalism are less numerous than in the generally used wooden 



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