Cytological Appraisal of a Bee eater, Merops orientalis

The present communication covers certain cytological aspects of a Coraciiform bird, Merops orientalis. Chromosome preparations were obtained from bone-marrow cells, following the air-drying technique of Garg ^{[1, 2, 3]}; Garg & Garg ^{[4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]} and Garg et. al. ^{[15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}. Based on the criterion of arm ratio/centromeric index, chromosomes were classified according to the scheme proposed by Levan et al. (1964).

The bone-marrow cells of five male and three female specimens yielded thirty two well spread metaphase plates for cytological investigation. The diploid count varied between 80 and 85 with the most prominent peak at 82. There were 17 pairs of macrochromosomes, divisible into three groups : metacentric {only Z}, sub-telocentric {8 pairs} and telocentric {8 pairs}.  Z was found to be the largest chromosome (_L^R = 9.54%), whereas W was a sub-metacentric chromosome, measuring 3.99%.

The remaining 24 pairs, most of them were either telocentric or acrocentric, together constituted 28.98% of Total Chromosomal Length.