Chenopod and amaranth pollen: electron-microscopic identification

Electron-microscopic criteria for distinguishing chenopod and amaranth pollen have been found in the number of minute holes and spinules, and especially in the ratio between them, which is 1.5 in amaranths and 1.6 in chenopods. Sixty-eight percent of total fossil pollen from a Classic Maya level (carbon-14 age 1380 +/- 120 B.P.) in a lake-sediment core from El Salvador belongs to wild amaranths, which presumably invaded corn fields. Fossil chenopodiaceous pollen from a depth of 3.85 meters (about 4000 years old) at Tinte, the Netherlands, is mostly Atriplex littoralis, which was evidently very common on coastal marshes in the middle sub-Boreal period.

Umbrella Pine, Sciadopitys verticillata: Past and Present Distribution in Japan

The umbrella pine, Sciadopitys verticillata S. and Z., a native Japanese conifer species and the only present member of the genus Sciadopitys, has become rapidly restricted in its geographic distribution since the beginning of intensified human activities. In Japan the genus was more widely distributed throughout the Pliocene and in the postglacial hypsithermal and slightly later times (R IIIa). In other parts of the world the genus has not appeared in the fossil record since the early Pleistocene. Conservation of this species is needed.