Authors’ addendum to: Comparative Study of the Karyotypes of Several Species in Carnivora, Including the Giant Panda (<i>Ailuropoda melanoleuca</i>)

Senior author’s address: Dr. Rosemary E. Newnham, Department of Haematology, King’s College Hospital Medical School, Denmark Hill, London (England). Since the publication of our above-named paper, we have received a further skin biopsy from the male spectacled bear, Tremarctos ornatus (F. Cuvier, 1825). A fibroblast culture has been established from this, and numerous good metaphase plates for chromosomal analysis have been obtained. It is now possible to state that the chromosome number is definitely 52, which is within the range we suggested previously. The karyotype is shown in the Figure. There are fifteen pairs of metacentric autosomes and ten pairs of acrocentric autosomes, one pair of which has satellites, similar to, but even larger than, those of the giant panda and the raccoon (K. Benirschke, personal communication). The X is a large metacentric chromosome; the Y is the smallest chromosome and is acrocentric. There are 80 major autosomal arms (N.F.), as in the bears. It is interesting that this, the only South American bear, has a completely different karyotype from the other bears studied and yet the N.F. is identical. The characteristic satellites, on the other hand, link the spectacled bear with the giant panda and the raccoon. Newnham, Davidson Giant panda karyotype 157 1 1% # “Lfc# % · i * IT v*