diff --git a/code/polymorphism/README.md b/code/polymorphism/README.md
index 32e6338ff6648c511533081e2e0986606f5221dc..6f7a44158b4db869895e6bc9a62cdb6b3d8ed4a1 100644
--- a/code/polymorphism/README.md
+++ b/code/polymorphism/README.md
@@ -2,7 +2,7 @@
 ## Instructions for the "polymorphism" exercise
 
 * look at the code
-* open `test.cpp`
+* open `trypoly.cpp`
 * create a Pentagon, call its `perimeter` method
 * create an Hexagon, call its `perimeter` method
 * create an Hexagon, call its parent’s `perimeter` method
@@ -12,7 +12,7 @@
 ## Instructions for the "compiler chain" exercise
 
 * preprocess `Polygons.cpp` (`cpp` or `gcc -E -o output`)
-* compile `Polygons.o` and `test.o` (`g++ -c -o output`)
+* compile `Polygons.o` and `trypoly.o` (`g++ -c -o output`)
 * use `nm` to check symbols in '.o' files
 * look at the `Makefile`
 * try `make clean; make`