diff --git a/Cantera/src/base/misc.cpp b/Cantera/src/base/misc.cpp
index 30d8d9a90..b8893514e 100644
--- a/Cantera/src/base/misc.cpp
+++ b/Cantera/src/base/misc.cpp
@@ -439,6 +439,8 @@ namespace Cantera {
       //! Typedef for map between a thread and the message
       typedef std::map< cthreadId_t, pMessages_t > threadMsgMap_t ;
 
+      //! Class that stores thread messages for each thread, and retrieves them
+      //! based on the thread id.
       class ThreadMessages
       {
       public: