Entomology definition of Fourth longitudinal vein September 8, 2014 Raj Entomology Dictionary 0 Please Like Us!!! DesiGoogly.com > Education News > Entomology Dictionary > Entomology definition of Fourth longitudinal vein Entomology definition of Fourth longitudinal vein: Diptera (Will.), = media 2 (Comst.). Entomology Fourth longitudinal vein definitionFourth longitudinal vein Entomology explanationFourth longitudinal vein Entomology meaningReviews & Comments