(n.) The natural history of fishes; that branch of zoology which relates to fishes, including their structure, classification, and habits.
Example Sentences:
(1) In the course of ichthyological inventory investigations in the main water-course of the Narew River the occurrence of Tracheliastes polycolpus Nordm.
Ichthyornis
Definition:
(n.) An extinct genus of toothed birds found in the American Cretaceous formation. It is remarkable for having biconcave vertebrae, and sharp, conical teeth set in sockets. Its wings were well developed. It is the type of the order Odontotormae.