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A study of the nucleoli of certain insects and the crayfish
Author(s) -
Johnson Mychyle W.
Publication year - 1938
Publication title -
journal of morphology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.652
H-Index - 74
eISSN - 1097-4687
pISSN - 0362-2525
DOI - 10.1002/jmor.1050620107
Subject(s) - nucleolus , biology , chromatin , crayfish , microbiology and biotechnology , evolutionary biology , nucleus , ecology , genetics , gene
Nucleoli in the germ cells of certain Orthoptera, Hemiptera and the crayfish have been studied. In Ceuthophilus (camel cricket) these bodies are found to be definitely connected with chromatin threads and are believed to be products of chromatin. The large structure in the ova of Nemobius (cricket) is interpreted as a nucleolus because of its very irregular behavior and apparent complete disappearance. It is found that some of the nucleoli of Gelastocoris (toad bug) arise within the chromatin threads. Observations on Cambarus (crayfish) fail to show nucleolar extrusion, a phenomenon which has formerly been reported for this form. The unique behavior and fate of the nucleolar material in Pselliopus (true bug) is described. In this species the nucleolar material is added to and becomes part of the general oxychromatin network of the nucleus. This study fully supports the opinion that nucleoli have a chromatin origin.