116 NATURAL HISTORY 
were these long feathers fixed only in the back, as 
may be seen by the turkey-cock when in a strutting 
attitude. By a strong, muscular vibration, these 
birds can make the shafts ‘of their long feathers 
clatter like the swords of a sword-dancer ; they 
then trample very quick with their feet, and run 
backward. 
LETTER XXXVI. 
Selborne, 177]. 
Dear Sizr,—Tue summer through I have seen 
but two of that large species of bat which I call 
vespertilio altivolans, from its manner of feng 
high in the air. 
‘In the extent of their wings they measured four- 
