Harbor porpoise (Phocaena Phocaena) (D) with full-term calf (blue) with tail partially extruded in the initial stage of birth (from doi: 10.1371 / journal. pone.0004366.g014.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

Genus Phocaena -- The Porpoises 260.    From Wordnik.com.  [Natural History of the Mammalia of India and Ceylon] Reference