--- a/MIMETypes.st	Tue Feb 20 21:52:42 2018 +0100
+++ b/MIMETypes.st	Thu Mar 01 10:49:27 2018 +0100
@@ -1109,10 +1109,10 @@
 !
 
 mimeTypeOfData:someData suffix:fileNameSuffixOrNilIfUnknown
-    "this tries to guess the mime type of contents of someData.
+    "this tries to guess the mime type of someData.
      Returns nil, if unknown.
      In addition to registered detectors (see addMimeTypeDetector:),
-     this is done using some heuristics, and may need some improvement"
+     this is done using heuristics, and may need some improvement"
 
     |buffer lcBuffer size idx idx2|
 
@@ -1199,6 +1199,7 @@
             ('Application create:'      #'application/x-smalltalk-source')
             ('becomeDefault!!'           #'application/x-smalltalk-source')
             ('(reader defineClass:'     #'application/x-smalltalk-source')      "/ gravel smalltalk
+            ('(define '                 #'application/x-scheme-source')      
 
     ) pairsDo:[:pattern :what | 
         (lcBuffer findString:pattern) ~~ 0 ifTrue:[