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W H Petri

Publications and source records attributed to W H Petri.

7 recordsLinked to original sources
PubMed1979

Structural and image analysis of a crystalline layer from dipteran eggshell.

A crystalline layer has been identified as a constituent of the eggshell in the dipteran Drosophila melanogaster. This 400A thick intermediate chorionic layer (ICL) is composed of eight 50A thick sublayers and lies between the vitelline membrane and the endochorion. Whole mount views of isolated ICL after negative staining reveal P2 planar periodicity which, when analyzed further by optical diffraction and filtering, showed 1st (100A), 2nd, 3rd and 4th order reflections.

Animals↗
PubMed1976

Three dimensional structure of the endochorion in wild type Drosophila melanogaster.

The endochorion of the Drosophila melanogaster eggshell has been isolated and its structure examined by transmission and scanning electron microscopy. In the main shell the thin inner endochorion (floor) shows small pits or pores and characteristic fenestrae crossed by irregular strands; vertical columns surrounded by air spaces separate this layer from the thick outer endochorion (roof) which is covered by a regular, external reticulum of thin fibers. The endochorion of the respiratory horns has sharply divided dorsal and ventral surfaces, with characteristic structures somewhat reminiscent of the floor and the external reticulum of the roof, respectively.

Animals↗