Chop up the insides of the baby marrow. It'll be tender, so it'll chop easily. Place all the chopped marrow in a colander over the sink, and sprinkle with a teaspoon of salt. Let it sit 10-15 minutes or until some water has been released, then futher squeeze out as much liquid as you can.
Add the eggs, the parsley, the flour, crushed garlic, the black pepper and salt, and combine until well mixed. It will form a thick batter. Set it aside while you heat the stove.
In a large deep skillet, add enough olive oil to coat the bottom. Heat on medium high heat until olive oil is hot. Scoop 2 tbsp sized dollops of the fritter batter into the hot oil. Don't add too many fritters at once, they shouldn't touch each other. You'll fry in batches!
Sautee for for 2-3 minutes a side until deep golden brown, then flip and cook on the other side for 2 minutes or so. Remove the fritters and place them on paper towel lined plate to absorb some of the oil.
Keep sauteeing until the batter is all finished, and enjoy warm or room temperature!