The optical and H I properties for a sample of low surface brightness ( LSB ) dwarf galaxies , cataloged from the Second Palomar Sky Survey , is presented .
Gas mass fractions for LSB dwarfs reach the highest levels of any know galaxy type ( f _ { g } = 95 % ) confirming that their low stellar densities are due to inefficient conversion of gas mass into stellar mass .
Comparison with star formation models indicates that the blue optical colors of LSB dwarfs is not due to low metallicity or recent star formation and can only be explained by a dominant stellar population that is less than 5 Gyrs in mean age .
If star formation occurs in OB complexes , similar to normal galaxies , then LSB dwarfs must undergo weak bursts traveling over the extent of the galaxy to maintain their LSB nature , which contributes to their irregular morphological appearance .