The Genetics of the Grouse Locust Tettigidea parvipennis Harris

Abstract

The color and morphological patterns of the grouse locust Tettigidea parvipennis Harris, have been used in analysing their genetic constitution. Bellamy (1917) (1) and MacQueen (unpublished thesis, 1938) (2) have reported previous investigations. The breeding method used by Nabours (3) with other species of grouse locusts has been followed. Individuals containing the patterns to be analysed were mated to others with contrasting patterns and the segregation showing in the offspring was recorded. The earliest hatches recorded appeared thirteen days after mating. The offspring were counted and transferred to new jars soon after hatching. The males were separated from the females after the first male became adult, approximately one week in advance of female maturity and four weeks from the time of hatching. The color pattern and wing length records were made with adults because only after the final ecdysis could the length of the wings be determined. The patterns studied are as follows (in their respective chromosomal groups): +/+-wild type, a grayish-black color with a crisscross marking; acts as complement to other color patterns in completing Mendelian ratios.