References in periodicals archive ?
Jamaican fossil echini. Memoirs of the Museum of Comparative Zoology, Harvard, 50, pp.
Pollen size is 143(mu)m, exine 3.5(mu)m thick, echini 9(mu)m high, echini base 5(mu)m wide, echini apexes 25.3(mu)m apart, inter echini base distance 18(mu)m, pore diameter 5(mu)m.
A report on the Echini of the warmer eastern Pacific based on the collections of the Velero III.