The name sea slug is most often applied to nudibranchs, as well as to a paraphyletic set of other marine gastropods without obvious shells. sea cucumber also looks slug-like and is sometimes loosely called a sea slug, but it is not a gastropod. Sea slug is a common name which is applied to some marine invertebrates that more or less resemble terrestrial slugs.
Clue: Vertebrae formations. Vertebrae formations is a crossword puzzle clue that we have spotted 3 times. There are related clues (shown below). Referring crossword puzzle answers. Likely related crossword puzzle clues.
The sacrum is formed by the fusion of 5 (sometimes 6) vertebrae known as the sacral vertebrae named as S1 to S5. Initially they exist as separate vertebrae, and begin to fuse after the age of 18. The fusion completes between the ages of 25 to 33. The last segment of the vertebral column is a structure called coccyx or tailbone, and represents a vestigial tail in humans. It is formed by the fusion of four small vertebrae designated as Co1 to Co4.