and comes from another source.

On account of the intimate relation of dream fear to neurotic fear,
discussion of the former obliges me to refer to the latter. In a little
essay on "The Anxiety Neurosis,"[6] I maintained that neurotic fear has
its origin in the sexual life, and corresponds to a libido which has
been turned away from its object and has not succeeded in being applied.
From this formula, which has since proved its validity more and more
clearly, we may deduce the conclusion that the content of anxiety dreams
is of a sexual nature, the libido belonging to which content has been
transformed into fear.

[1] To sit for the painter. Goethe: "And if he has no backside, how can
the nobleman sit?"

[2] I myself regret the introduction of such passages from the
psychopathology of hysteria, which, because of their fragmentary
representation and of being torn from all connection with the subject,
cannot have a very enlightening influence. If these passages are capable
of throwing light upon the intimate relations between the dream and the
psychoneuroses, they have served the purpose for which I have taken them
up.

[3] Something like the smoked salmon in the dream of the deferred
supper.

[4] It often happens that a dream is told incompletely, and that a
recollection of the omitted portions appear only in the course of the
analysis. These portions subsequently fitted in, regularly furnish the
key to the interpretation. _Cf._ below, about forgetting in dreams.