Fibrilae or Fibrillae: How To spell?
The word Fibrilae is misspelled against Fibrillae, which is plural of "Fibrilla"
Fibrillae has double "ll" is mispronounced as "l"Remember double 'LL' in between the strings fibri & ae which should not be misspelled with single 'L'
Wrong Spelling:  fibri-l-ae  Correct Spelling:  fibri-ll-ae 
Find more wrongly spelled words of Fibrillae to spell it well.