Definition of "fourling"

Every 67th lying-in woman has twins, every 5333rd has trillings, and only every 150,000th has fourlings.

1842, “Sweden as it is; Moral, Political and Statistical”, in The Foreign Quarterly Review, volume 28, number 55, page 449

this breed is prominent for its remarkable fecundity and yield of milk; as a rule, this goat litters once a year and drops 2 kids; occasionally trillings and fourlings.

1922, The Goat World, Devoted to the Upbuilding of the Goat Industry, page 67

If the two or the four first cells into which the animal ovum divides during the process of so-called cleavage be separated from one another, then each of these cells grows into a small but complete organism. Conversely, if two ova be caused to amalgamate with parallel axes, the result is a "giant". What is the meaning of this? It is, that the material which, if left undisturbed, would have grown into one, can grow into many-into twins or into fourlings. And similarly the material destined for many may furnish one only.

1929, Hans Dreisch (W.H. Johnston), Man and the Universe, page 93