  A characterisation of quantum stochastic positive definite (PD) exponent is
given in terms of the conditional positive definiteness (CPD) of their
form-generator. The pseudo-Hilbert dilation of the stochastic form-generator
and the pre-Hilbert dilation of the corresponding dissipator is found. The
structure of quasi-Poisson stochastic generators giving rise to a quantum
stochastic birth processes is studied.
