Divination in this tradition is not a lookup. A person goes to a diviner they or their house have a relationship with, sits through a procedure, and receives something addressed to their circumstances. The sign is one input among several, and the diviner is not an interface to a table.
That is worth saying because a reference page invites the opposite reading. A list of sixteen signs with meanings beside them presents divination as a decoding operation, which is a distortion whatever the meanings said. The apparatus is public; the practice is not, and the practice is the part that matters to a practitioner.
It also explains why the record thins where it does. What can be written down about a relationship is mostly its outward form, and the outward form is what ethnography has documented well.
Metanla, the thirteen-mouth throw, is the first of the four upper signs named by their shell count. The atlas records its position, its rarity and the naming convention it belongs to, all of which are structural and checkable. Its interpretive content is conferred within initiated Lucumi practice and is not reproduced in this entry.
The person consulting has a part in it as well. They bring a question, they are present while the shells are cast, and what they take away is shaped by their own standing in the house and by what they are prepared to undertake. None of that is recoverable from a shell count, and a page presenting one would be describing an event with the people taken out of it.