182 THE ESSEX FIELD CLUB.
hay at Ongar. There was some apprehension in that district as to whether
there was any possibility of a locust plague arising there next year. He did
not suppose, however, that the locust was likely to breed and thrive in a
climate like ours. He had suggested to Mr. Mugleston, farmer, of East
Hanningfield, who was in possession of a number of locusts, that he should
send them to Mr. Cole—not with a view of having the Secretary eaten up by
these voracious insects next season [laughter]—but in order that all that was
possible might be found out about them,
Mr. E. A. Fitch thought that there need be no apprehension of a locust
plague in Essex. The specimen produced was a mature locust, and, remembering
an "exhibit" (in the medical sense) of dried edible locusts at the Entomological
Society some years ago, in which he and Mr. Cole participated, he rather
thought the Secretary would eat the locusts, instead of the locusts eating the
Secretary [laughter].
Professor Meldola said it was encouraging to know that the locust was not
likely to become an additional cause of agricultural depression.
[These specimens of locusts are referred to in a note in the present number,
see p. 196.]
Rev. W. Linton Wilson exhibited specimens of the "cherry-gall" of the oak,
Dryophania scutellaris, from Epping Forest.
Mr. J. T, Cunningham, M.A., of the Marine Biological Laboratory, Plymouth,
and Lecturer on Fisheries and Oyster Culture to the Essex County Council, then
delivered a very able and interesting discourse on the transformations of marine
animals. The lecture was illustrated by many beautiful and original slides,
shown by the oxy-hydrogen lantern. Mr. Cunningham first dealt with the
transformations of Jelly-fishes, and the phenomena called "Alternation of Gene-
rations," or Metagenesis. He then treated of the main facts in the development
of the Echinodermata—Starfishes, Sea-Urchins, and Feather-Stars (Crinodea).
The transformations among the Crustacea were next described, the Zoea stages,
and the remarkable "retrograde development" of the "Barnacles" and "Acorn-
Shells" (Cirripedia) as studied by Darwin.
The lecturer then dealt with the transformations among fishes, showing the
remarkable differences in the development of the various species of flat fish, and
followed with a lucid explanation of the theory of evolution among fishes, and
the causes of their hereditary modification. He also alluded to the great problem
of modern biology raised by the German savant Weismann, who holds that there is
no transmission of acquired characters. The lecturer thought that the facts of
metamorphosis and recapitulation could not be explained logically on this assump-
tion. He said : We could not at present form any conception of the manner in which
changes produced in the body by the conditions of life could affect the properties
of the germ cells in such a way as to reproduce those changes in the offspring.
For instance, the asymmetry of the eyes in the flat fish might be caused in indi-
viduals by the strains and pressures due to the new horizontal position of the
fish on the sea-bottom ; but we cannot understand how the asymmetry so pro-
duced could become hereditary, how the change in the structure of the head
could have any effect on the eggs and sperms. On the other hand, on the hypo-
thesis that all hereditary changes have originated in the germ-cells, there is no
reason why the older history of the race should be recapitulated in the develop-
ment of the individual. On this hypothesis, the egg of the flat fish ought to