Spermatocyte chromosome analysis of Helicella virgata (Pulmonata: Helicidae): silver-stained and C-banded chromosomes.

Chromosome numbers of the snail Helicella virgata from the fields of Castellammare del Golfo (Sicily) are n = 26 and 2n = 52. Silver-staining analyses of testicular cells suggest that both mitotic and meiotic chromosomes are involved in nucleolus organization. A within-individual variability in NOR-banding pattern is present in each of the 20 specimens analyzed.