The PartList
In the System16 Info Block, there is the entry 'Offset to the PartitionList(Relative to System16's Base Address)' at offset 112, that points to this block. It's a chained structure with information on all partitions accessable to the V2_OS. Each entry is 32bytes long.

Ofs Size Description
0 5 Partition Name, lowercase, terminated with a zero. Example'hda1',0 or 'fd0',0 or 'hdb',0 etc.
6 1 Physical Disknumber (from the DiskList)
7 4 First sector of this partition (in LBA)
11 4 Amount of sectors in this partition
15 1 Reserved
16 4 DiskName like 'fd0',0 or 'hdb' etc. (0 terminated)
20 ... Reserved

This table can be displayed by using the 'partlist' command from the command-prompt.