same specimen, view of the opening between anal shield and thoracic shield, exposing head and collum (reduced first tergite) usually held inside the sphere when rolled up  
  Part of: Wilbrandt J, Lee P, Read H, Wesener T (2015) A first integrative study of the identity and origins of the British Dwarf Pill Millipede populations, Trachysphaeracf.lobata (Diplopoda, Glomerida, Glomeridae). Biodiversity Data Journal 3: e5176. https://doi.org/10.3897/BDJ.3.e5176