"Writers entrapped by / teatime fame and by / commuters' comforts?"
One of the interpretations of the poem, albeit a less popular one, is that it refers to Moore's own writing of her poetry. This is one of the best lines to give credence to that interpretation, as it seemingly lambasts writers who focus on their fame at the expense of their craft (Moore often wrote to her literary peers that she didn't even feel like publishing her work sometimes). It also mocks the sorts of written work that would appeal to the proletarian commuters who want something soft, easy, and easily digested for their morning ride to work. Moore's oblique and often intimidating verse would certainly not apply. She does not care, though, and makes her "paper nautilus" for herself and herself only.
"the intensively / watched eggs coming from / the shell free it when they are freed"
This is fascinating commentary on motherhood and childbirth. The beautiful shell that the mother has spent so much time making and protecting will be destroyed once the children come forth. This is act of violence, regardless of whether or not it is biological, as is the ravaging of the human mother's body during pregnancy and childbirth. Furthermore, all of the nurturing and love and protection is over once the children issue forth into the world. They are free from their mother and no doubt relish that freedom, but it is bittersweet for the mother who knows that her "fortress" was the only truly safe place.
"round which the arms had / wound themselves as if they knew love / is the only fortress / strong enough to trust to"
Moore doesn't often talk about platitudes like motherly love in her poems, and in true Moore fashion this evocation of love comes at the end of the poem about a sea creature and her eggs. Also in true Moore fashion, the love is somewhat obsessive, suffocating. The image is of legs wrapped around the shell, and the shell is referred to as a "fortress." No one is getting out of the mother's embrace, and when they do, they ought to remember how it was the only safe place in the world.
