Chromosomes of the following four species ofPolisteswasps from the Bryan-College Station area in Texas are reported:apachus, n = 22 or 25; exclamans, n = 33;metricus, n = 26; and carolina, n = 19, 2n = 38. The karyotype of P. carolinawas constructed and revealed that chromosomes no. 16 and no. 19 are acrocentric whereas the others are metacentric.