River facing river, silver confronts black;
Right reflecting left, fields become birds;
Night pierces day.

Yin and yang, female and male;
Inside–outside, inseparable;
Plus and minus, light and shade.

Tessellations and intertices
Interlock
Interstices and tessellations.

Shade and light, minus and plus;
inseparable outside-inside;
Male and female, yang and yin.

Day pierces night;
Birds become fields, left reflecting right;
Black confronts silver, river facing river:

Night and Day.

What’s the unusual feature of this form? It's a word palindrome. The sequence of words is the same whether you read them in the normal way, or backwards from the end to the beginning. The title is part of the palindrome.

Palindromic poems based on letter reversal are much harder to write, which is probably why there are very few in existence that make much sense.