prominent, that the processes on the bones for the attachments of muscles were not so well marked, that its muscular structure was more delicate, that the skin was softer, and finer, and freer from wrinkles, that the nail was longer in proportion to its width than that of man. Such would be the description of an average female thumb, as I see thumbs belonging to the ladies of my acquaintance.
Now, following Miss Gardener in the offer which she makes, and according to which—by my ability to select rightly in every instance—I am to gain or lose my case, I make this proposition to her:
I will agree to furnish twenty well-preserved thumbs, marked in cipher, if subjects can be obtained for the experiment, Miss Gardener or her "twenty leading brain-anatomists," etc., to divide the male from the female thumbs, by applying any knowledge they may possess on the subject.
Doubtless Miss Gardener and the "twenty leading brain-anatomists," etc., know a male from a female thumb when they see them, but I am quite sure that by judicious selection, I should be able to confound their judgment. I should take some of the male thumbs from small, delicate men who had never done any hard work, and who had taken good care of their hands by wearing gloves and availing themselves of the services of a manicure, while I should select some female thumbs from women whose hands are hardened and enlarged by exposure and toil, and to whom nail-brushes and soap-and-water are rarities. I am quite safe in saying that Miss Gardener and the "twenty leading brain-anatomists," etc., would find it impossible to select the ten male from the ten female thumbs, and I am equally certain that there is not an anatomist of the brain kind, or any other variety, who could accomplish the feat.
That there are female brains that are larger than male brains, of altogether superior development, and the possessors of which have greater intellectual power than is exhibited by some men, neither I nor any any one else, so far as I know, has ever denied. Miss Gardener can not be in ignorance of my views on this subject, for she quotes my words "average male and average female brain," and it is to the "average" female brain only that my description applies. A fair proposition would be the following, and, if Miss Gardener, from the resources at her command—"the collections" of the "twenty leading brain-anatomists," etc.—will supply the brains, I will agree to stand or fall by the result. Weigh one hundred male brains and then one hundred female brains: if the average weight of the male brains is not several ounces greater than that of the female brains, I lose my case. The only condition I make is that I shall be present when the brains are selected and weighed.
It is scarcely necessary, however, to repeat an experiment that has been performed by many anatomists in all parts of the civilized world. Thus, Welcker's observations show that the average male brain in Europeans is a little over forty-nine ounces, and the average female brain a little over forty-four ounces, a difference of about five ounces. The proportion existing between the two is therefore as 100:90. Huschke found the brains of adult man and woman to weigh respectively 1,410 grammes and 1,272 grammes. His observations, therefore, coincide very exactly with those of Welcker.
Calori not only found that the brain of man is heavier than that of woman, but he discovered the fact that the difference exists no matter what may be the form of the skull. Thus in men with brachycephalic skulls, the average weight of the brain was 1,805 grammes, while in brachycephalic women it was only 1,150 grammes. In the dolicocephali the average weight of the male brain was 1,282 grammes, whereas that of the female brain was 1,136 grammes.
Broca, in his paper "Sur le volume et la forme du cerveau," arranges from Wagner's elaborate table one which shows that this difference exists for all ages from twenty-one years to sixty and over. The results are given in grammes in the following table:
| AGE | MEAN WEIGHT OF BRAIN. | |
| Men. | Women. | |
| From 21 to 30 years | 1,341·53 | 1,249 |
| From 31 to 40 years | 1,410·36 | 1,262 |
| From 41 to 50 years | 1,391·41 | 1,261 |
| From 51 to 60 years | 1,341·19 | 1,286·13 |
| From 61 upward | 1,326·21 | 1,208·43 |
In fact, all authorities, without exception, save Miss Gardener and the "twenty leading brain-anatomists," etc., agree that the average European male brain is about five ounces heavier than the average female brain.
Another test that I am willing to abide by is the following, relating to the other characteristics that Miss Gardener quotes as having been laid down by me:
Let her, from the stores at her command, allow me to select from at least one hundred specimens an average female brain, and from a like number an average male brain. I will agree to point out to a competent brain-anatomist—not one of the "twenty," however—all the differences for which I have ever contended. By that test also I am willing to stand or fall.
I have never said, as Miss Gardener charges, that the sex of an infant could be determined by its brain, though Rüdinger declares that a typical point of difference be-
