The 37 Nats of Burma

"The nats of Burma make up a structured system of animistic spirits,
predating the advent of Theravāda Buddhism but coexisting with it and
with other systems of divination and prediction such as astronomy and alchemy."

The Sentient Beings according to the Burmese. Buddhist Cosmogony.

"The Burmese ideas of Sentient Beings, borrowed from India, represent a philosophy dealing with the evolution of the soul. First, in the Nether Worlds we have the evil soul, then in the present world we have the normal soul of man, rising to the higher soul of the angel in the nearer heavens. Next we have the soul getting the better of the body in the Rúpá world of the higher angels, and lastly, the soul dissociated from the body in the Arúpá, or immaterial, worlds, waiting for Nirvána or diccolution". In the Burmese Buddihist Cosmogony, all living beings are divided into three classes: - Kamá, generating; Rúpá, corporeal ungenerated; Arúpá, incorporeal. These three classes are a divided into thirty-one species, each with its bón (bhúmi, place, state, stage, region) or seat. [...] "

No. 1. Thagyá nat. No. 2. Mahágirí nat.

21. Maung Pó Tú nat. 22. Yun Bayìn nat.

A Burmese map of the world, showing traces
of Medieval European map-making.

Hell according to the Burmese.

"In the centre are those who are undergoing various punishments. Below these is depicted an unfortunate about to enter and begging for mercy, and near him is to be seen another who is reluctant to go forward and is being dragged and goaded onward. At the bottom of the picture is Thagyá judging the deceased; behind him are the four executioners. At the four corners are the abodes of the four great executioners -Yamahlá, Yamada, Yamaká and Yamamin, the abode of the last being represented as empty"

The thirty-seven nats, a phase of spirit-worship prevailing in Burma, by Sir R. C. Temple. With full-page and other illustrations. (published 1906) at NYPL
(where I spent way, way too much time today - like a child in a toyshop).

• Some background from BookRags.
• Spirit worship in SE Asia - 'Nat in my Classroom' - lecture notes originally from North Georgia College + State University.