Nerydes or Nereides: How To spell?

The word Nerydes is misspelled against Nereides, which is plural of "Nereid"

Word contains consecutive vowels 'EI' in between alphabets ner & des is misspelled as 'Y'
Wrong Spelling:  ner-y-des 
Correct Spelling:  ner-ei-des 
Explore spell check of Nereides to spell without errors.