The Design and Evolution of C++; Ch. 3, p.64 - Bjarne Stroustrup
Based on that excerpt, I'd hazard to guess that there was never was a C+. If there where, it's extremely unlikely that its Stoustrup participated in its creation.
That list is not complete. There are plenty of niche languages not present. (The X*PLOR programming language, used in an old crystallography program, and the SVL programming language, used in the molecular structure program MOE, are not present.) But it means that C+ is at best obscure.
anaccountname/Zellio: I've seen that story about the naming logic for C++ (primarily the incrementer operater bit) which is what triggered my initial suspicion of this C+(no more pluses) thing.
Judging by the responses thus far and the propensity of HN to punish the uninformed question I am feeling relatively secure in my original assertion to the other programmer who originated this argument that there is in fact no such language as C+ (excluding of course something some random guy made that was never used in any significant volume). That said if I am wrong please let me know, cheers.