It can make fine visual distinctions because it is blessed with one million cones per squaremillimeter in its retina.
它的视网膜上每平方毫米有一百万个视锥细胞，所以它能分辨出很细微的视觉差别。
2
There might be a couple hundred of these color sacks per squaremillimeter of the octopus' skin, and depending on the species, they can come in as many as five different colors.
章鱼每平方毫米的皮肤上可能有几百个这样的色袋，根据章鱼品种的不同，色袋可以有多达五种不同的颜色。
3
In fact, one squaremillimeter of cortex has more than 100,000 neurons.