Many older PDF scans found on the web are problematic due to:
Hand-written manuscripts or old 19th-century lithographs can be blurry and hard to read for students.
"Hayat al-Hayawan al-Kubra" by Kamal al-Din Muhammad ibn Musa al-Damiri is an Arabic zoological encyclopedia from the 8th century. SifatuSafwa Ad - Damiris Hayat Al - Haywan Vol 1 : Jayakar, A. S. G.
Whether an animal is halal or haram to eat.