Terminology: convex indifference curves

From an article by A. Kozlik in the American Economic Review, Mar 1941.

I was asked about the expression used in one of the first year problems sheets, "convex to the origin", when asked to describe the usual way economists draw indifference curves (i.e., when they satisfy a diminishing marginal rate of substitution- = get flatter -as you move to the right). Clearly our terminology has been inconsistent for a long time. The textbook uses the expression "bowed to the origin". The above article argues that (c) is the best solution, but I am not sure his recommendations were ever taken seriously.