<P> The list of cloud types is a summary of classifications and photographs . The ten main genus - types in the troposphere are grouped into altitude - levels; high (cirrus, cirrocumulus, cirrostratus), middle (altocumulus, altostratus), multi-level (nimbostratus, cumulus, cumulonimbus), and low (stratocumulus, stratus). Small cumulus are commonly grouped with the low clouds because they do not show significant vertical extent . Of the multi-level genus - types, those with the greatest convective activity are often grouped separately as towering vertical </P> <P> The genera are also grouped into five physical forms . These are, in approximate ascending order of instability or convective activity: stratiform sheets; cirriform wisps and patches; stratocumuliform patches, rolls, and ripples; cumuliform heaps, and cumulonimbiform towers that often have complex structures . Most genera are divided into species, some of which are common to more than one genus . Most genera and species can be subdivided into varieties, also with Latin names, some of which are common to more than one genus or species . The essentials of the modern nomenclature system for tropospheric clouds were proposed by Luke Howard, a British manufacturing chemist and an amateur meteorologist with broad interests in science, in an 1802 presentation to the Askesian Society . </P>

What are some names of some types of clouds