Striated Muscles of an Amber Insect

Abstract

IT is well known that arthropods found in Baltic amber are unusually well preserved, so that even the minutest features of their chitinous structures are plainly visible under considerable magnification. The internal organs, however, are usually completely disintegrated, nothing but the amber mould of the chitinous skeleton remaining. It was therefore something of a pleasant surprise to discover a specimen of an amber fungus-gnat in which the flexor and extensor muscles of the tibia, located in the femur, are so well preserved in all legs, that not only their outlines, but also the transverse striations of the fibres, may be clearly seen under the microscope at a linear magnification of 300:1 (see Fig. 1).