AMONG the many interesting features suggested by the genealogical table in last week's NATURE (p. 40), showing the persistence of abnormality in the number of toes on a cat's paw, there is one the significance of which seems not to have occurred to, or to have been passed over by, Mr. Edward Poulton. The peculiarity I refer to is the larger percentage of abnormality among the female offspring than among the male. Taking “Tabby V.” as a starting-point, and leaving out one aonormal kitten of which the sex was unnoted, as well as the families of which no particulars are given, the cocal number of descendants in the table is 36, of which 12 are males and 24 females. Of the 12 males, 5 are normal and 7 abnormal, or 41 2 3 and 58 1 3 per cent, respectively; and among the 24 females 7 are normal and 17 abnormal, or 29 1 6 and 70 5 6 per cent. respectively. Or, to put it in another way, among the 12 normal kittens 5 are males, 7 are females, or 41 2 3 and 58 1 3 per cent, respectively, instead of 33 1 3 and 66 2 3 per cent. as it should be; and among the abnormals 7 are males and 17 females, or 29 1 6 and 70 5 6 per cent, instead of 33 1 3 and 66 2 3 .
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