This inheritance list is sorted roughly, but not completely, alphabetically:

[detail level 12]

CAdjacencyList< LinkData, NodeData >	This class provides a static adjacency list data structure
CBasixElementData< T >	Basix element holder
CBoundingBoxTree< T >
CComm	A duplicate MPI communicator and manage lifetime of the communicator
CConstant< T >	Constant (in space) value which can be attached to a Form
CCoordinateElement< T >
CDirichletBC< T, U >
CDofMap	Degree-of-freedom map
CElementDofLayout
CEntityMap	A bidirectional map relating entities in one topology to another
CExpression< T, U >	An Expression represents a mathematical expression evaluated at a pre-defined points on a reference cell
Cfalse_type
Cdependent_false< T >
CFiniteElement< T >
CFiniteElement< T >	Model of a finite element
CForm< T, U >	A representation of finite element variational forms
CFunction< T, U >
CFunctionSpace< T >	This class represents a finite element function space defined by a mesh, a finite element, and a local-to-global map of the degrees-of-freedom
CGeometry< T >	Geometry stores the geometry imposed on a mesh
CHyperElasticProblem	Hyperelastic problem class
CIdentityPartitionerPlaceholder	Placeholder for the creation of an identity partitioner in refine
CIndexMap
Cintegral_data< T, U >	Represents integral data, containing the kernel, and a list of entities to integrate over and the indicies of the coefficient functions (relative to the Form) active for this integral
CMatrixCSR< Scalar, Container, ColContainer, RowPtrContainer >	Distributed sparse matrix using compressed sparse row storage
CMesh< T >	A Mesh consists of a set of connected and numbered mesh topological entities, and geometry data
CMeshTags< T >	MeshTags associate values with mesh topology entities
Cmpi_type_mapping< T >	MPI Type
CPointOwnershipData< T >	Information on the ownership of points distributed across processes
CScatterer< Container >	A Scatterer supports the scattering and gathering of distributed data that is associated with a common::IndexMap, using MPI
CSparsityPattern
CTable	This class provides storage and pretty-printing for tables
CTimeLogger	Time logger maintaining data collected by Timer, if registered
CTimer< T >	Timer for measuring and logging elapsed time durations
CTopology	Topology stores the topology of a mesh, consisting of mesh entities and connectivity (incidence relations for the mesh entities)
CVector< T, Container, ScatterContainer >	A vector that can be distributed across processes
CVTKFile	Output of meshes and functions in VTK/ParaView format
CXDMFFile	Read and write mesh::Mesh, fem::Function and other objects in XDMF