Figure 5. Major karyotypes of the grammicus complex. Karyotypic modifications which differ from the primitive or standard condition are enclosed within the black borders. If the condition is fixed the border is solid, and if polymorphic the border is dashed. A. standard (S), B. polymorphic-1 (P1), C. fission-6 (F6), D. fission-5 (F5), E. fissions 5+6 (F5+6), F. multiple fissions (FMl) [Note that the FIS-3 mutation is present in the population at a low frequency, although this individual is homozygous metacentric for pair 3], G. multiple fissions (FM2) [Note that there is an "extra" pair of microchromosomes in this pattern, possibly resulting from a fissioning of micro-chromosome pair 14]. The bar between pairs 3 and 4 in column D represents 10 micrometers.