PYATRAS P. GRISHKYAVICHUS,63, first secretary of the Communist Party of the Soviet Baltic republic of Lithuania since 1974, died Nov. 14. Accounts of his death, carried by Tass, the official Soviet news agency, did not report the cause of his death or where he died.

After the 1941 German invasion of Lithuania, Mr. Grishkyavichus, a member of the Komsomol Communist Youth League, fled eastward with the Red Army. He fought with the Soviet forces during World War II, and was parachuted into German-occupied Lithuania in 1943, where he joined a partisan unit. He held various administrative posts in the republic's party apparatus and was named party boss in Vilnius, Lithuania's capital, in 1971.

PIETER NICOLAAS MENTEN, 88, a millionaire art collector who was unmasked as a war criminal after he tried to sell pieces from his collection which included World War II Nazi SS plunder from Poland, died Nov. 14 at a nursing home in Loosdrecht, Netherlands. The cause of death was not reported.

Sentenced to 10 years in jail in 1980 for crimes in Poland during World War II, he was released earlier this year after serving two-thirds of his term. He had been found guilty, as a collaborator of the Nazi SS, of involvement in the murder of 120 Jews, whose remains were found in a mass grave in the village of Podhorodze in 1976.

YIGAL SHILOH, 50, who was head of the Archaeological Institute at Hebrew University from 1983 to 1986, and who supervised the excavations in the City of David outside Jerusalem's walled Old City, died Nov. 14 in Jerusalem. The cause of death was not reported.

As head of the City of David archeological team, Dr. Shiloh explored the origins of Jerusalem from the period of the Canaanites until the time of the kings of Judah -- 1190 B.C. to 965 B.C. He also participated in major archeological expeditions at Masada, a southern mountaintop fortress destroyed by the Romans in the year 73, and Megiddo, an ancient northern city inhabited since the 4th millennium B.C.

HARRY RUSAN, 77, a retired Ford Motor Co. millwright who had been one of the original clown princes of basketball with the Harlem Globetrotters, died Nov. 9 at a hospital in Detroit. The cause of death was not reported.

Mr. Rusan was a 5-foot-7 forward who averaged nearly 20 points a game while playing for the Globetrotters from 1934 to 1939. He established scoring records during three successive seasons and was named to the All-Time Globetrotter Team by owner Abe Saperstein.

JULIUS GABRIS,74, one of the four Roman Catholic bishops in Czechoslovakia, who had been bishop of Trnava, in Slovakia, since 1973, died Nov. 13 in Prague. The cause of death was not reported.

His death leaves only three of the country's 13 Roman Catholic bishoprics headed by bishops. Since 1973, negotiations between the Vatican and the Czechoslovak government have stalled because of Prague's unwillingness to approve clergymen proposed for bishoprics by the church.