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of the lobster, is at hand. While unavoidable delay in the drawings prevents 
placing the complete matter in your hands, it is quite possible to give you in 
a few words a general idea of the results and their bearings, such as will no 
doubt sufliciently answer your questions, 
According to the arrangements made, some of the eggs from berried lobsters 
kept for the purpose were sent me at regular intervals through an entire year. 
These eggs were at once examined to note their progress in development, and 
they were then preserved by various methods for future studies and compari- 
sons. After their young were hatched the females themselves were dissected, 
to observe the condition of the ovaries, and to determine the time when another 
lot of eggs. might have been expected from them. As our work began in 
midwinter, it was necessary to follow certain specimens up to the hatching, 
and then to take others to complete the series from the laying. Eggs supplied ~ 
me as freshly laid were so far advanced as to indicate that fertilization had 
taken place before they were placed under the tail of the lobster bearing them. 
The time and process of fertilization has not been discovered ; but in all likeli- 
hood the marine lobster does not differ greatly in these respects from its fresh- 
water relatives, the crayfishes. In the case of the latter the male seeks the 
female some time before the eggs are laid, and deposits the fertilizing matter 
on the upper side of the body, near the external openings of the oviducts, 
where it adheres for a time as a whitish mass. How the fertilizing elements, 
the spermatozoa, come into contact with the eggs and enter them, has not yet 
been observed. The development of the embryo in eggs laid on the seventh 
or eighth of August was so rapid that on the third of September the eyes were 
visible as thin crescent-shaped spots. As the waters grew colder the progress 
was retarded, until the changes were very slight indeed. This condition was 
maintained throughout the winter, and it was only when the summer tempera- 
ture was reached that rapidity of advancement was again to be noted. The 
young began to hatch on the fourteenth of July ; all of the eggs on a female 
seeming to be about equally advanced, the entire brood emerged at very nearly 
the same time. Examination of the ovaries, after their young had left, showed 
that the females would not have laid eggs again for a year ; that is, not before 
the summer next following that in which they had hatched a brood. In other 
words, the dissections proved that the lobster lays only once in two years, 
hatching a brood one summer and laying eggs the next following summer for 
another brood. The time required in the development of the embryo is so 
long as to preclude hatching the eggs under ordinary circumstances during 
the summer in which they are laid. Artificial conditions might readily be 
brought about, by heating the water in which the specimens are kept, which 
would hasten the progress and greatly shorten the period between laying and 
hatching ; but normally the winter temperature induces an almost complete 
suspension of advancement. 
By the small number of specimens kept, it was not possible to fix the lengths 
of either the laying or the hatching periods. This, however, may be approxi- 
mately done in connection with observations made by the United States Fish 
