Assertion: gastropod's teeth | /r/AtLocation | the middle of rows
Facets:
value: by addition
type: MANNER
value: by the division of existing teeth
type: MANNER
Source sentences:
text: A number of teeth occur on each row; this number is usually constant but prone to small variations from row to row; indeed, it increases over time, with teeth being added to the middle of rows by addition or by the division of existing teeth.