Dilated

"Now the rays of yellow being more refracted by the first Superficies of the said Air than those of red, are thereby made more oblique to the second Superficies, at which they are reflected to produce the colour'd Rings, and consequently the yellow Circle in each Ring will be more dilated than the red; and the Excess of its Dilatation will be so much the greater, by how much the greater is the obliquity of the Rays, until at last it become of equal extent with the red of the same Ring."

"The sternum forms a long, linear, deeply channeled lobe, between the coxæ, the apex very dilated, cordate, with a very elevated ridge in the centre, like a nose in profile"