arachnoidea

In 1905 he became an assistant in the Crustacea, Arachnoidea, and Myriapoda collection of the museum.

The arachnoid mater covering the brain is referred to as the "arachnoidea encephali", and the portion covering the spinal cord as the "arachnoidea spinalis".

The canal is lined by a membrane resembling the tunica arachnoidea, and is situated above the fissure of the medulla, being separated by a medullary layer: it is most easily distinguished where the large nerves are given off in the bend of the neck and sacrum, imperceptibly terminating in the cauda equina.