Examination of 42 testicular cells fromH. americanusyielded a diploid chromosome number of 110 with a range of 94 to 185. The diploid number inH. gammaruswas determined to be 95.5 with a range of 90.5 to 134.5 The meiotic chromosome number ofH. americanuswas found to be bimodal at 66.5 and 68. The meiotic chromosome number inH. gammaruswas 62.5. The range of meiotic chromosome counts inH. americanuswas 50.5 to 83.5. InH. gammarusthe range was 45 to 88.