Emphases mine.

The best part about Middlemarch’s Dorothea Brooke is how much she wants to be a boy undergraduate and for her husband to be college. [I finally did finish Middlemarch!] Based solely on Middlemarch and Daniel Deronda, George Eliot’s personal ranking of womanly beauty goes something like this:

Good: Beautiful. You know how. Like a bird, and so on, full of blondness and a superfluity of curves, mouth full of teeth, etc. A little horrifying, but also pleasant.

Better: Plain, but tempered with pleasing maturity, and sharing in the inheritance of ten thousand good human foremothers. Like a Dutch painting that knows how to laugh at itself, or a reliable little partridge, stoutly dressed for dinner.

Best: Looks like a boy looks like a boy looks like a boy!! looks like a BOY! she looks like a fella, she’s a girl what looks like a serious young man. What if there were a girl…with the face of a boy…and the mind and heart of a wonderful boy…and she was the most wonderful girl in the world…If George Eliot were judging a beauty pageant, Yentl would win every time.

“You see how widely we differ, Sir James. I have made up my mind that I ought not to be a perfect horsewoman, and so I should never correspond to your pattern of a lady.” Dorothea looked straight before her, and spoke with cold brusquerie, very much with the air of a handsome boy, in amusing contrast with the solicitous amiability of her admirer.

Husbands are wonderful because they are boys, but old husbands are even better because they can teach you Greek and Latin, the official language of boys:

She would not have asked Mr. Casaubon at once to teach her the languages, dreading of all things to be tiresome instead of helpful; but it was not entirely out of devotion to her future husband that she wished to know Latin and Greek. Those provinces of masculine knowledge seemed to her a standing-ground from which all truth could be seen more truly…
However, Mr. Casaubon consented to listen and teach for an hour together, like a schoolmaster of little boys, or rather like a lover, to whom a mistress’s elementary ignorance and difficulties have a touching fitness. Few scholars would have disliked teaching the alphabet under such circumstances.

“Wanting to be a boy is what ruins the best women,” –George Eliot, 1871.

“Oh dear,” said Dorothea, taking up that thought into the chief current of her anxiety; “I see it must be very difficult to do anything good. I have often felt since I have been in Rome that most of our lives would look much uglier and more bungling than the pictures, if they could be put on the wall.” Dorothea parted her lips again as if she were going to say more, but changed her mind and paused.
“You are too young—it is an anachronism for you to have such thoughts,” said Will, energetically, with a quick shake of the head habitual to him. “You talk as if you had never known any youth. It is monstrous — as if you had had a vision of Hades in your childhood, like the boy in the legend. You have been brought up in some of those horrible notions that choose the sweetest women to devour — like Minotaurs. And now you will go and be shut up in that stone prison at Lowick: you will be buried alive. It makes me savage to think of it! I would rather never have seen you than think of you with such a prospect.”

If you take “dilettante” as code for “effeminate,” Henry James’ writing about Ladislaw makes a lot more sense: “Dorothea is almost a boy, which is terrific, and Ladislaw is almost a girl, which is terrible,” thereby setting the stage for a lot of problems in the twentieth century.

Will went along with a small book under his arm and a hand in each side-pocket, never reading, but chanting a little, as he made scenes of what would happen in church and coming out. He was experimenting in tunes to suit some words of his own, sometimes trying a ready-made melody, sometimes improvising. The words were not exactly a hymn, but they certainly fitted his Sunday experience:—
Sometimes, when he took off his hat, shaking his head backward, and showing his delicate throat as he sang, he looked like an incarnation of the spring whose spirit filled the air—a bright creature, abundant in uncertain promises.

At this point in Middlemarch, Dorothea has essentially transmogrified into a prayer-book and Ladislaw is halfway between a hummingbird and a scarf. It’s terrific.

Raffles on his side had not the same eagerness for a collision which was implied in Ladislaw’s threatening air. The slim young fellow with his girl’s complexion looked like a tiger-cat ready to spring on him. Under such circumstances Mr. Raffles’s pleasure in annoying his company was kept in abeyance.

Being a horseless rascal is as near to being a woman as it is possible to get without really putting your back into it:

“Yes, I have tried everything—I really have. I should have had a hundred and thirty pounds ready but for a misfortune with a horse which I was about to sell. My uncle had given me eighty pounds, and I paid away thirty with my old horse in order to get another which I was going to sell for eighty or more—I meant to go without a horse—but now it has turned out vicious and lamed itself. I wish I and the horses too had been at the devil, before I had brought this on you. There’s no one else I care so much for: you and Mrs. Garth have always been so kind to me. However, it’s no use saying that. You will always think me a rascal now.”
Fred turned round and hurried out of the room, conscious that he was getting rather womanish, and feeling confusedly that his being sorry was not of much use to the Garths.

We’re in Deronda territory now, and everyone finds themselves closer to gender-swapping the closer they get to falling in love – the likeliest crucible for transition, at least in Eliot, is developing a crush, bonus points if your crush happens to be on a luminous, full-lipped boy with a swanlike throat, or a ruinously willful girl who lives on the back of a horse and wears a necktie.

Poor Rex felt his heart swelling and comporting itself as if it had been no better than a girl’s.

Daniel Deronda, Male Tomboy:

The deep blush, which had come when he first started up, gradually subsided; but his features kept that indescribable look of subdued activity which often accompanies a new mental survey of familiar facts. He had not lived with other boys, and his mind showed the same blending of child’s ignorance with surprising knowledge which is oftener seen in bright girls. Having read Shakespeare as well as a great deal of history, he could have talked with the wisdom of a bookish child about men who were born out of wedlock and were held unfortunate in consequence, being under disadvantages which required them to be a sort of heroes if they were to work themselves up to an equal standing with their legally born brothers.

“Sylph” belongs to that great old collection of words meaning “Androgyny of the particular sort usually belonging to men” rather than “Androgyny of the particular sort usually belonging to women.”

Her observation of matrimony had inclined her to think it rather a dreary state in which a woman could not do what she liked, had more children than were desirable, was consequently dull, and became irrevocably immersed in humdrum. Of course marriage was social promotion; she could not look forward to a single life; but promotions have sometimes to be taken with bitter herbs—a peerage will not quite do instead of leadership to the man who meant to lead; and this delicate-limbed sylph of twenty meant to lead.

“I remember being a boy — it reminded me a great deal of being a woman — boys and women share a united indignation at the freedoms of gentlemen”:

He was beginning to feel on Mirah’s behalf something of what he had felt for himself in his seraphic boyish time, when Sir Hugo asked him if he would like to be a great singer—an indignant dislike to her being remarked on in a free and easy way, as if she were an imported commodity disdainfully paid for by the fashionable public.

Whoops!!!

She still kept her hand in his and looked at him examiningly; while his chief consciousness was that her eyes were piercing and her face so mobile that the next moment she might look like a different person. For even while she was examining him there was a play of the brow and nostril which made a tacit language. Deronda dared no movement, not able to conceive what sort of manifestation her feeling demanded; but he felt himself changing color like a girl, and yet wondering at his own lack of emotion; he had lived through so many ideal meetings with his mother, and they had seemed more real than this! He could not even conjecture in what language she would speak to him. He imagined it would not be English. Suddenly, she let fall his hand, and placed both hers on his shoulders, while her face gave out a flash of admiration in which every worn line disappeared and seemed to leave a restored youth.
“You are a beautiful creature!” she said, in a low melodious voice, with syllables which had what might be called a foreign but agreeable outline. “I knew you would be.” Then she kissed him on each cheek, and he returned the kisses. But it was something like a greeting between royalties.

Oh, can’t he????!

“I beseech you to tell me what moved you—when you were young, I mean—to take the course you did,” said Deronda, trying by this reference to the past to escape from what to him was the heart-rending piteousness of this mingled suffering and defiance. “I gather that my grandfather opposed your bent to be an artist. Though my own experience has been quite different, I enter into the painfulness of your struggle. I can imagine the hardship of an enforced renunciation.”
“No,” said the Princess, shaking her head and folding her arms with an air of decision. “You are not a woman. You may try—but you can never imagine what it is to have a man’s force of genius in you, and yet to suffer the slavery of being a girl.”

This one’s a little tricky to follow, but as best as I can sum it up, Mirah’s appealing look reminds Daniel of how much he’s always loved womanhood, ever since his lip was a girl’s lip – her eyes have sent his eyes back into a past where every mouth was Girl. Pretty straightforward stuff, once again brought to you by George Eliot’s Straightforward Gender Emporium.

But now he dared avow to himself the hidden selection of his love. Since the hour when he left the house at Chelsea in full-hearted silence under the effect of Mirah’s farewell look and words—their exquisite appealingness stirring in him that deep-laid care for womanhood which had begun when his own lip was like a girl’s—her hold on his feeling had helped him to be blameless in word and deed under the difficult circumstances we know of. There seemed no likelihood that he could ever woo this creature who had become dear to him amidst associations that forbade wooing; yet she had taken her place in his soul as a beloved type—reducing the power of other fascination and making a difference in it that became deficiency.

The Chatner

George Eliot's Boyish Girls and Girlish Boys