  The composition of present day cosmic rays (CRs) is inconsistent with a
significant acceleration of SN ejecta material (even with a preferential
acceleration of ejecta grain material). Current CRs must result mainly from the
acceleration of ISM ("solar mix") and circumstellar (22Ne- and 12C-rich WR
wind) gas and grain material. The CR source composition, indeed, shows no
anomaly related to SN nucleosynthesis: (i) The CR source FeNi/MgSiCa ratios
have precisely solar mix values, while FeNi are mainly synthesized in SN Ia's,
and MgSiCa in SN II's. If CR's originate in SN ejecta, this requires tight
conditions on the acceleration efficiencies of the various SN Ia's and SN II's.
(ii) The non-deficiency of the main-s-process elements, not made in any SN,
relative to all elements made in SNae. (iii) All CR source isotope ratios are
consistent with solar mix (except for the 22Ne and 12C excesses, WR wind). (iv)
The absence of 59Ni in CRs implies that the time delay between the SN
nucleosynthesis and their acceleration is > 10^5 yr. (v) The physics of SNR's
and of CR shock acceleration implies that the acceleration of interior ejecta
material is comparatively insignificant (Ellison & Meyer, this volume).
Predominant acceleration of current CRs out of superbubble material also seems
implausible. These conclusions regarding current CRs do not necessarily
conflict with the linear evolution of Be/H in the early Galaxy. With the near
absence of heavy elements in the early Galactic ISM, indeed, the acceleration
of even a minute amount of freshly processed material must have then played a
dominant role for the generation of Be from C and O. The "Be indicator" is
blind to a possibly dominant early Galactic CR component originating in the ISM
then composed of virtually pure H and He.
