How many letters does the top answer for “a description of animals, their forms and habits.” have?

The most common answer is zooegraphy (10 letters).

Crossword clue: a description of animals, their forms and habits.

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

zooegraphy 10 letters web-def

A description of animals, their forms and habits.

zoography 9 letters web-def

A description of animals, their forms and habits.

one who describes animals, their forms and habits. 50% similar → zooegrapher, zoographer