REPORT OF COMMISSIONERS OF INLAND FISHERIES. 99 



III. The Attainment of Normal Length in the Appendages. 



Under this subject we will first consider whether the thoracic ap- 

 pendages or legs ivill attain nor^nal length at the first moult. 



Some investigators have maintained that the walking legs do attain 

 the normal length at the first moult. The well-known zoologist, 

 Brooks, for example, made the following observations on the w^alk- 

 ing legs in a study of the European lobster, Homarus vulgaris: "After 

 the ecdysis (moult) the new ambulatory limbs assumed all the pro- 

 portions of their uninjured fellows, * * * ^}-iis evidence shows 

 that in the lobster, at any rate, the new aml^ulatory limbs attain 

 their full development at the first ecdysis." He further proceeds 

 to interpret this fact by remarking that, indeed, this is what we might 

 be led to expect for the following reasons : A study of the functions 

 of the different limbs shows that the chelipeds may still be of great 

 service, even though they have not attained the normal length ; but 

 that it is different in the case of the walking appendages — a walking 

 leg would be of little use to the lobster if it were much smaller than 

 its fellows, and therefore there is a natural provision for the resto- 

 ration of a walking leg to the normal size at the first moult.* 



In regard to this question my observations do not support these 

 conclusions. On the contrary, in the present experiments on a 

 large number of lobsters, the ambulatory appendages did not thus 

 attain their normal length at the first moult, as may be seen in the 

 following tabulated data on five of these lobsters: 



♦Brooks. Notes on Reproduction of Lost Parts in the Lobster {Homarus vulgaris). Roy. 

 Physical See, session CXVL, pp. 370-385; 1887. 



