<prompt> Black malarial pigment is seen in: September 2009P.vivaxP.falciparumP.nialariaeP.ovlae  <response>: Ans. B: P.falciparum In well-stained preparations the nuclei of the parasites are always stained red and the cytoplasm blue. The presence of malaria pigment is very characteristic of the older stages of Plasmodium sp. P. falciparum often contains a single black dot. P. vivax often contains countless fine golden yellowbrown specks of malaria pigment. In P. ovale and P. malariae the pigment inclusions are many and brownish black. Countless fine red spots in the red blood cell Schiiffners dots can be seen in P. vivax and P. ovale the more mature the parasite, the more dots. In P. ovale the dots are sometimes called Jamess dots. Sometimes a few flecks can be observed in P. falciparum Maurers dots or clefts. P. malariae almost never exhibits dots Ziemanns dots. The visibility of these dots depends to a great extent on the acidity pH with which the thin slide preparation is stained slightly alkaline: pH 8 is best. The acidity is impoant because blood smears are usually stained for haematological tests with a slightly acid pH. 