FELINES (Finding and Examining Lots of Intron 'N' Exon Sequences) is a utility written to automate construction and analysis of high quality intron and exon sequence databases produced from EST (expressed sequence tag) to genomic sequence alignments. We demonstrated the various programs of the FELINES utility by creating intron and exon sequence databases for the fungal organism Schizosaccharomyces pombe from alignments of EST to genomic sequences. In addition, we analyzed our constructed S.pombe sequence databases and the well-established Saccharomyces cerevisiae intron database from Manuel Ares' Laboratory for conserved sequence motifs. FELINES was shown to be useful for characterizing branchsites, polypyrimidine tracts and 5' and 3' splice sites in the intron databases and exonic splicing enhancers (ESEs) in S.pombe exons. FELINES is available at http://www.genome.ou.edu/informatics.html.