[stevenkh1]

I think I found the answer to my question in an old article by Charles A White in the Bulletin of the Torrey Botanical Club (published in 1901):

"My observations were made while engaged in amateur gardening upon my house-lot in Washington D.C. and were briefly as follows: In the spring of 1898 I purchased from a dealer in Washington two dozen tomato plants of the Acme variety and transplanted them in my small garden. They produced a uniform crop, both fruit and plants answering in all respects to the reputed characteristics of Acme, the plants of which variety are typical representatives of the atavic group. I selected seeds from fruit of the best plants of the crop and planted them in the same garden plot in 1899, expecting to grow another crop of Acme tomatoes from them. The seeds germinated promptly and the crop of thirty young plants grew well, but from their first appearance above ground they showed a marked difference from Acme plants. When they had reached the fruiting stage, they had developed into typical representatives of the solanoid group, and not of their parent atavic group; showing the difference from their parent form was more than varietal in character. Furthermore, every plant of the crop possessed identically the same characteristics, all having shared equally and fully in the mutation. The new form was varietally characterized by an excellent quality of fruit, but it was different in flavor and shade of color from that of the Acme, and ripened earlier than did that of the parent plants. I saved no seed from the fruit of the new variety and therefore supposed it to be lost, as indeed it was.

"In 1900 I planted in the same garden-plot Acme tomato seed which I purchased from a seedsman who grew it on a Pennsylvania farm, more than a hundred miles from the place where the seed of my first crop was grown. These seeds also produced a uniform crop of typical Acme plants and fruit. I selected seeds from fruit of the best of that crop of thirty Acme plants and sowed them in my garden in the spring of 1901, and grew in that year also thirty plants from those seeds, again expecting to get a harvest of Acme tomatoes. On the contrary, the result was an exact duplication of my experience in 1899, every plant and every fruit partaking fully and uniformly in the duplicated mutation.

"One naturally inquires whether mutation of any other variety than the Acme would have occurred in my garden, whether it is an inherent quality of that variety to give only one mutative result, and that toward the solanoid group, and what are the natural and artificial conditions of my garden. I have made no experiments with any other variety than the Acme and its progeny, the new one, and can therefore only refer to these. The Acme variety is now twenty-five years old, and has been one of the most stable of the many known varieties of tomato; but of late years it has shown so much tendency to atavic reversion that gardeners are abandoning its cultivation."

So it appears after 25 or go generations, Livingston's Acme mutates so it may explain why it appears to be extinct. There is another account discussing the same issue featured in Science (November 29, 1901) as well.