A cytogenetic study on the Bolivian squirrel monkeys (Saimiri boliviensis boliviensis), maintained in Tsukuba Primate Center for Medical Science of the National Institute of Health, has been carried out. The chromosome number is 44. The autosomes consist of 15 non-acrocentric and 6 acrocentric chromosome pairs. The X and the Y are the metacentric and the smallest acrocentric chromosomes, respectively. The Nos. 4 and 6 chromosomes show interstitial C-band variations. The variations of chromosome 4 are confirmed as a Mendelian genetic character by a genetic analysis of the offspring among them. The C-band size differences of the chromosome 6, however, are not clear whether a genetical or a artificially induced difference at present.

View full abstract

Detailed aspects of the lingual papillae of the Japanese monkey (Macaca fuscata fuscata) were examined by the scanning electron microscope. On the lingual dorsum and margin, four kinds of the lingual papillae were observed; filiform, fungiform, vallate and foliate papillae. Locational variations were seen on the filiform papillae as follows; the circle-arranged papillae with a single one in their center on the lingual apical area, the large conical papilla with a pair of spines on the lingual body and the small aggregated papillae on the lingual radical area. The fungiform papillae also showed locational variations; globular shape on the apical area and cylindrical on the middle area. Four vallate papillae, being large and round, were located in an inverted V-shape immediately anterior to the terminal sulcus. Well-developed foliate papillae, numbering 15-20, were arranged in the shape of pillars on the posterior area of the lingual margin. No locational variations were found on the vallate and foliate papillae.
Referring to the morphological variations of the filiform papillae, it can be said that locational differences on the lingual dorsum may be revealed by forms adaptable to acquired habits, although the basic form of the papillae are to be aggregated in the primates. The fungiform papillae may show morphological variations according to the number of the taste buds in their developmental process.

View full abstract

The People's Republic of Congo, in central Africa, has large and dense forests in parts of the north and south-west. The northern tropical forest, especially the Bomassa area in Sangha province, has been subject to very little scientific inquiry. I carried out a preliminary investigation on the primate fauna in the Bomassa area using the line transect method along 32.6km of elephant trails over 8 days in October 1988. The main survey area was about 85km north-east of Ouesso, the central city of Sangha province.
The vegetation is composed of riverside forest, a grassland-like Marantaceae domain with Gilbertiodendron dewevrei (Caesalpiniaceae) and swamp. These 3 types of vegetation are distributed mosaicly. Some parts are flooded during the rainy season. Five genera consisting of 10 species of primates (Cercocebus galeritus agilis, C. albigena, Cercopithecus cephus, C. nictitans, C. pogonias, C. neglectus, Colobus guereza, C. badius, Pan troglodytes and Gorilla g. gorilla) were identified by direct observation during the census. The presence of Colobus badius was newly recorded in this region. Cercocebus albigena, Cercopithecus nictitans, and C. pogonias are considered to be the most abundant species. This area has never been disturbed by human activity and should provide a useful ecological model for many fields of research and for conservation.

View full abstract