Gogarty warned my ancestor, nzred fanobrel, that it was only an approximation. According to this analysis, the germ-cell of a given sex has forty-nine chromosomes, seven each of Types A, B, C, D, E, F, six of Type G and one of Type H—the last, Type H, being the sex determinant. Six mobile gametes are formed through meiosis—each containing an identical group of seven chromosomes of Types A through G—and a seventh or stationary gamete containing chromosomes A, B, C, D, E, F, and H. This last Gogarty called the female or H gamete, since it never leaves the body of the Plookh until the fully fertilized cell of forty-nine chromosomes—or seven gametes—is formed, and since it determines sex. The sex, of course, is that of the Plookh in whose body it is stationary.”

“Of course,” Shlestertrap murmured and conjugated long and thoughtfully with the bottle.

“It has to be, since that is the only H chromosome in the final zygote. But you know that for yourself. In fact, operating with a human intelligence, you have probably anticipated me and already extrapolated the whole process from the few facts I have mentioned.”

Moisture gathered at the top of our civilizer’s head and rolled down his face in the quaintest of patterns. “I understand you,” he admitted, “and of course I’ve already figured out the whole thing. But just to make it clear in your own mind, don’t you think you might as well continue?”

I thanked him for his unfailing human courtesy. “Now, if it is a srob with whom we start our chain, it will transmit one of its six mobile gametes to a mlenb where the gamete will unite with one of the mlenb’s A through G cells, forming what Gogarty called a double-gamete or pre-zygote. This pre-zygote will contain seven pairs of A through G chromosomes, and, in the body of the tkan—next in the chain—it will unite with a tkan mobile gamete forming a triple-gamete with seven triplets of A through G chromosomes.