of the Fishery Board for Scotland. 103 
lobster the larger the number of eggs which it carried. A lobster 10 
inches long had 8000 eggs, while oue 15 inches in length bore 32,000. 
Herrick found in the American lobster that the number of eggs varied 
from 3000 to 70,000. The eggs of two lobsters were estimated at the 
Laboratory in the following manner:—They were snipped off the 
swimmerets and dried in a water-bath. A small portion was detached 
and weighed, the number of eggs in it was counted, and the total 
number was got from the total weight. One measuring 114 inches in length, 
11,309 eggs, while the other, 12} inches long, had the same number. 
It is remarkable that so small a number of fry was obtained from the 
parent lobsters kept in the Bay of Nigg. This is partly accounted for 
from the fact that a greater or less quantity of the eggs is lost when the 
berried hens are handled, and during transport. This does not, however, 
seem sufficient to account for the whole of the shortage. 
HAtTcHine. 
Hatching occurred at the Laboratory during July, August, and Sep- 
tember. The earliest larve appeared about the middle of July, the 
majority hatched in August, and a few in September. 
According to Coste* hatching takes place in March, April, and May. 
Allen records that hatching took place in one instance in March. Fabre- 
Domergue, and Biétrix f observed the hatching of the lobster, and 
describe the process in detail. The larve issue early in the night. 
The whole brood of any one female does not hatch out at once, but 
over a period, the larvee issuing in two or more batches (vide Coste, Herrick, 
and Fullarton). The incubation period, according to Ehrenbaum, Herrick, 
and Fullarton, is about eleven months. During an incubation period so 
extended it is to be expected that a certain variation will have occurred 
in the point of development reached by different eggs. This would result 
in spreading the hatching of the eggs over a period which probably does 
not usually exceed a fortnight or three weeks, The first larval lobsters 
were observed on July 11th, and one of the females was found to have 
hatched all her eggs on August 2nd. The larve usually appeared in 
the morning. 
MEASUREMENTS OF THE LOBSTER. 
Occasionally lobsters are measured by the length of their barrels, 2.e. of 
the carapace, from the extremity of the rostrum to the hind border. In 
several cases the relation between the total length and the length of the 
barrel has been noted, and the data are entered below. 
Total Length of Lobster, | Length of Barrel. 
Q 94 inches. 4,3. inches. 
2103, Ea Oe 
: iat » ty 7 
2 ” OTs ” 
123 29 53 ” 
eS er 5S oy 
| 
| 
* Vide Buckland. 
+ Fish Trades Gazette, Sept. 26, 1903. 
