Delthyris
Delthyris , noun
[New Latin, from Greek de`lta the name of the letter D + thy`ra door.]
(Zoology) A name formerly given to certain Silurian brachiopod shells of the genus Spirifer.
Collocations (1)
Delthyris limestone (Geology) , one of the divisions of the Upper Silurian rocks in New York.