Picprochiciion of Lost Parts in the Lohstcr. 3 / 9 



point were both males. These facts must be borne in mind, 

 as, according to Chantran's observations on adult crayfish, 

 the male moults twice as often as the female. Although I 

 have no definite information on the subject for the lobster, 

 it appears probable that a similar diversity exists in this 

 species. 



In Lobster B. the rioht chela was lost at a time when the 

 left had a pincer joint 3 inches in length. After the next 

 ecdysis the right chela was reproduced, its pincer joint 

 measuring 2f inches in length. With the same ecdysis the 

 left pincer joint had increased from 3 to 3f inches in 

 length. After an ecdysis which took place four months later, 

 the left pincer was 3| inches long and the right of inches. 

 Thus w4th the second ecdysis the difference in size between 

 right and left pincer joints was reduced from 1 inch to J inch. 

 The next ecdysis did not take place until the following 

 spring, eight months after the second. The difference be- 

 tween the two was then reduced to J inch, and after a fourth 

 ecdysis during the autumn this difference was maintained. 



From these observations we may conclude that in a male 

 lobster, about 7^ inches in length, if one of the chelae is lost, 

 a period of from sixteen to eighteen months intervenes before 

 the new limb attains its full and normal development for a 

 lobster which in the interval has attained a length of about 

 9 J inches. These results agi'ee closely with Chantran's 

 observations on Astaciis. 



Growth of CHELiE lost at Different Dates. 



The observations on Lobster C. afford interesting informa- 

 tion on the growth of chelse lost at different dates. The left 

 chela was lost 7, xii. 82, and the right 6, ii. 83, practically 

 two months afterwards. In the meantime the rudiment of 

 the left chela made its appearance, and during the following 

 month a similar rudiment was formed on the right side. On 

 13, iv. 83, the left rudiment was J inch long, and that on the 

 right side only I inch. During the months of May and 

 June the smaller rudiment increased more rapidly in size 

 than the one first formed, until on 26, vi. 83, both were 

 practically of the same size. A few days later ecdysis took 



