The common bottlenose dolphin is the largest species of the beaked dolphins. Genasauria is a clade of extinct beaked, primarily herbivorous dinosaurs. In addition, white sharks attack and prey upon beaked whales. Eight species of beaked whales occur in California's waters. The achenes are beaked and some species have feathery hairs attached to them. Ziphiids consist of 22 species of beaked whale. Very little is known about the life history of beaked whales. The crest is a demi-eagle displayed with two heads, sable beaked gules. Not much information is available about group composition of beaked whales. Their heads are beaked like a vulture's, while simultaneously sporting curved fangs. The stigmas are head-like, narrowed or often beaked. Fruit that bears a prominent pointed terminal projection is said to be "beaked". The plague doctors of Nijmegen also wore beaked masks. Beaked whales consist of over 20 genera.