Is this a correct disk label?

[Peter Steele]

I have a USB disk that I partitioned with fdisk and bsdlabel. I used the -w option of bsdlabel to write a standard label. The label itself looks fine:

# bsdlabel da0s1
# /dev/da0s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  7823576       16    4.2BSD     2048 16384 28528
  c:  7823592        0    unused        0     0         # "raw" part, don't edit

What puzzles me are the entries I see under /dev/da*

# ll /dev/da0*
crw-r-----  1 root  operator    0, 181 Dec  3 15:29 /dev/da0
crw-r-----  1 root  operator    0, 183 Dec  3 15:29 /dev/da0s1
crw-r-----  1 root  operator    0, 185 Dec  3 15:29 /dev/da0s1a
crw-r-----  1 root  operator    0, 185 Dec  3 15:29 /dev/da0s1a
crw-r-----  1 root  operator    0, 186 Dec  3 15:29 /dev/da0s1c
crw-r-----  1 root  operator    0, 192 Dec  3 15:29 /dev/da0s1ca

Why are there two da0s1a entries and this da0s1ca entry? That doesn't look right to me.