The Sirenia reference article from the English Wikipedia on 24-Apr-2004
(provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Sirenia

Sirenia
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Sirenia
Families
 Dugongidae
 Trichechidae

Sirenia are herbivorous mammals of coastal waters. They have evolved aquatic adaptations: they have arms, which are modified into paddles, but no legs, are fat, and have highly modified skulls with greatly reduced dentition. Their nipples are under their arms (see the picture of a pair of manatees).

Mammals
Xenarthra | Dermoptera | Desmostylia | Scandentia | Primates | Rodentia | Lagomorpha | Insectivora | Chiroptera | Pholidota | Carnivora | Perissodactyla | Artiodactyla | Cetacea | Afrosoricida | Macroscelidea | Tubulidentata | Hyracoidea | Proboscidea | Sirenia
Monotremata
Didelphimorphia | Paucituberculata | Microbiotheria | Dasyuromorphia | Peramelemorphia | Notoryctemorphia | Diprotodontia