ABSTRACT
Three kinds of lipid bodies have been described in the oogenesis of the cockroach, Periplaneta americana: (i) L1 bodies, present in the earliest oocyte, which persist till the oocyte measures approximately 0·5 mm and contain phospholipids only, possibly having more lecithins than cephalins; (ii) L2 bodies, which first arise in the oocyte measuring 0·4 mm and have a complete or incomplete sheath of phospholipids sur-rounding a medulla of triglycerides (rather highly saturated); (iii) L3 bodies, which are the only type of lipids present in the oocytes measuring more than 0-65 mm and consist of triglycerides only (rather highly saturated).
Some of the larger L3 bodies give a ‘ringed’ or ‘crescentic’ appearance in Sudan black when used at room temperatures (12° C to 40° C) but appear mostly solid when this colouring agent is used at 6o° C.
Mitochondria, which remain as fine granules throughout the course of oogenesis, contain proteins and phospholipids. They seem to have some lipids which are masked normally but are unmasked after acetone extraction, with a resulting increase in sudanophilia.
Yolk globules appear in the oocytes measuring approximately 0 ·5 mm. They contain a protein-carbohydrate complex.
The bacterioid objects described by earlier workers have been shown to contain phospholipids and free fatty acids. They possibly play an active role in the lipid synthesis of the cell.
