Registers of macrofossils arranged by 1" (one inch ro the mile) or 1:50 000 scale English geological sheets. Each register is numbered 1-359 and each sheet has one or more volumes. Within each volume, data is arranged by collectors symbol. This is the system used in the Leeds office (the London office had a different system- see MACROLONDON). It is this system that is currently in use.

11 volumes of macrofossil and microfossil collections donated to IGS/BGS. Arranged sequentially in three series: LZ 1-10000 LZA 1-10000 LZB 1-10000 LZC 1-553