Answer: is not written with true feeling.
Faulkner implies in these lines that new literature is not written with true feeling. He tells us that it has "no universal bones," which means that it does not talk about things that matter to all humans. He also tells us that it "leaves no scars," which means that it does not significantly alter or impact the reader. Finally, Faulkner tells us that this type of writing speaks not of the heart but of the glands, which means that it is not poetic or artistic.
