92 Part LL1.—Twenty-third Annual Report 
Size (inches) of 
Size Soft Lobsters. I 5: Length 
: mmediate : 
No.| Month. (inches) Increase of Time 
; before | Measured | Measured a Si in 
Casting.) just after | after an i ig Captivity. 
the Cast. Interval. 
Inch. 
Pj¢ Saby, 123 122 13 0 1 Year. 
2 F 124 123 123 z a 
3 B: 102 10% Z Fs 
4 As 123 13 z 2 YEARS. 
5 BS 17 114 4 re 
6 " 113 113 4 1 YEAR. 
a, BS 112 112 3 of 
8 A 12 122 4 m 
9 Sept, 11 112 He 3 3 
10 Ce 93 i» | 103 ae | month. 
11 Oct. 112 12 | e = 1 Year. 
12 é 1 11,3 - ah 2 months. 
13 a: 114 z 2 ee 
14 Nov. 11 11 0 oe 
These figures indicate that there was no great increase in size just after 
the cast, whatever may happen during the time that the shell is harden- 
ing. Herrick found that the lobster grew considerably during that time. 
While most of the lobsters mentioned in the Table had been in captivity 
for a year or more, there are four cases in which the length of confine- 
ment was only that of a month or two. In the case of one lobster, | 
the increase in size nine mouths after the moult was one inch, 
In the other short-period cases the increase was just as small 
as with the lobsters which had been over a year in the Laboratory. 
In two cases, in fact, the soft lobster was, as far as could be 
ascertained, exactly the same size as the hard lobster, It was not 
possible to separate all the soft lobsters and measure them subsequently 
to see what increase took place during the hardening of the 
shell. In the case of the first two lobsters, which were re-measured, after 
intervals of two and one week respectively, an increase of $ inch in each 
case took place. Ehrenbaum agreed with the earlier observations of 
Herrick and Rathbun in noting the slowness in the growth of the older 
lobsters. He instances a case where a lobster, measuring 40°2em. (16 
inches) in length, only increased its length by a millimetre (; inch) on 
casting. Vitzou gives measurements to show the increase that takes 
place in different parts of the body after casting; he demonstrated the 
fact that while the carapace aud abdomen increased in size at once, the 
large claws only showed a marked increase 17 hours after the moult. 
Salter describes in detail the operation of casting. The lobster cast in 
July. Immediately after it had got rid of its shell it concealed itself 
among a mass of seaweed that it had before casting collected in a corner 
of the tank. Brook observed that a male lobster buried some food 
before casting, and after another cast it partially buried its cast integu- 
ment in the sand. 
