Cirostomi or Cirrostomi: How To spell?
The word Cirostomi is misspelled against Cirrostomi, a noun meaning "The lowest group of vertebrates; -- so called from the cirri around the mouth; the Leptocardia. See Amphioxus."
Cirrostomi has double "rr" is mispronounced as "r"Remember double 'RR' in between the strings ci & ostomi which should not be misspelled with single 'R'
Wrong Spelling:  ci-r-ostomi  Correct Spelling:  ci-rr-ostomi 
Find more incorrect spellings of Cirrostomi to spell right way.