Ewest - IMO the two different pictures by bz are probably due to the time frame in which they were taken, the darker of the two being taken when the HBG are in still in spawning/nesting mode in the spring and early summer. The second lighter picture is very recent and it is likely all spawning and nesting behavior has likley ceased for the year.
Just from my own observations and discussions on PB, in your std. hatchery cross, a male BG X female green sunfish cross the male offspring will exhibit more coloration and body characteristics of a green sunfish than a BG. In the natural HBG that I have seen in our pond between a female BG and a male green sunfish the male offspring have size and shape characterics mostly of a BG and will resemble a pumkinseed somewhat in appearance. To put it more simply, IMO the male offspring of crosses have a general tendency to heavily resemble the female of whatever parent species they are crossed with. Now I could be wrong so I am eager to hear other opinions, but that is my current thinking on this issue.
It will be intersting to see if Bruce gets some RES/BG hybrids. If I am right they should resemble RES much more than a BG due to the sex of the parents, male BG X female RES. I am guessing the gill rakes will look more like a RES than a BG. I would expect the opposite in a male RES X female BG cross.
