A systematic study of the absorption spectra of the benzologues of fluoranthene shows that the β- and β′-band of fluoranthene originate from two different absorptions of polarized light. The β′-band at 2360 Å results from polarization along the naphthalene complex and the β-band at 2870 Å from polarization perpendicular to it. A number of higher annellated fluoranthenes have been synthesized: 2:3,