Here are the data structures with brief descriptions:

CAccounting
CActiveReceptor
CBranchPoint
CCondState
CContextStore
CConversationState
CH
CIterationState
CL
CM
CMaddr
CMwalkState
CN
CPtrlist
CQ
CQe
CR
CReceptor
CReceptorAddress
CReceptorRoute
CrT
CS
CScape
Cscape_elem
CSemanticID
CSemTable
CSgroupClose
CSgroupOpen
CSliteral
CSocketListener
CSState
CStream
CSTypeData
CSvalue
CT
Ctable_elem
CTcontents
CTcontext
Cthread
CTstruct
CUT_hash_bucket
CUT_hash_handle
CUT_hash_table
CUUIDt
CVMHost
CXaddr