tcnpei-nture inust nlso correspond rr.tlier v;ell Virith tiiat xThich 

 the ser. ymter of the Moi-nTet;^ic.n YTest Goo.st reo.che.s during the 

 Icirval developiaont tine, thus in July-August. Ovdng to the 

 early hatching of the larvae in the Channel one nust assvine that 

 those have here a longer grov.-th period dtjring the first period 

 and therefore during this tine (in the first suimner and autu^.m) 

 reach a bigger si7.e and an older stage than on our coasts. 

 Hereupon the observations of Cmmingham indicate, as he f ound, 

 that Irrvce hatched out on the 23d to 30th ilay v.'ore on the 5th 

 August (probably) in the fifth stage with a lengbh of approxi- 

 riately 22 irua. There is hardly a douot that they have reached at 

 least the 8th or 9th stage before the conclusion of the first 

 grovrbh period. 



Concerning the grovjth cf the J^nerican species in the larval 

 stages as vrell as in the later stages one has— besides those nade 

 by lierrick— now thorough exardnations rado by Hadley and by Mead, 

 and YTillians. I cannot here closely review these interesting 

 vorks in detail., but I i.iust restrict nyself principally to give 

 the conclusions to which the workers have come. Hadley assunes 

 that the average fonale on the American coast reaches sexual 

 maturity in the 6th year (th'S 6th grovrt:h period) and in the 23d 

 stage. It is therefore supposed to coincide approxina.tely with 

 our category 2 (see p<> 53) in regard to the stage n-unberj that is 

 the number of noultings, but in regard to the age it should on 

 the average be considerably younger than this. He also assumes 

 that the femr.les afber they ?iave reached sexual maturity grcv/ 

 more slowly than the males. Besides the rn-iter points out that 

 the gro\Tbh also for the grown. animals-~ha5 varied on the diff- 

 erent sections of the /aaerican coast of the Atlantic Ocean. Tfith 

 regard to the dvur.tion of developmorrt of the larval stages this 

 coast with its varying physical conditions of the sea water 

 presents interesting variations. Yfliile during a few experiments 

 made nt Wickford, Rhode Island, at a temperature of approximately 

 18-|-22'^ C» the tliree first stages vrerc passed through in 9 to 16 

 <^^'Ciys, at Wood's Hole, llass. at a temperature 15-15-g-° C. 21 to 25 

 days moreover v/ere required. Furthermore it is related that 

 during development f^f the first three stages near Orr's Island 

 (Maine), at a temperature which varied betv/eon 14 and 17° C.^ 25 

 to 26 days vrere required for the sane stages (p. 200)^ on the more 

 southerly situated Rhode Island at a temperature of 22-24° C» only 

 9 to 10 days v/ero necessaryo Interesting is the agreement in 

 regard to the speed of development T.rhich the larvae she? on both 

 sides o.f the Atlantic Ocean as soon as the temperatxire conditions 

 become sonev/hat equal. ■' A comparison betv;eer. these two conditions 

 made at Orr's Island and on our West Coast shows this agreement 

 very clearly. In relation to the grovfth of the latter stages— which, 

 to Judge inoreover from Herrick and Hadley' s ta.bles (see Hadley, 

 Table 13, ps 182), appears .to presenb as strong individual variat- 

 ions as on our ooasts-«»direct comparisons can hardly be made 

 betvireen our species and the American one because vie lack direct 

 observations on the latter, Hadley's results in regard to the 



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