
          Cambridge, Saturday, July 7th


 Dear Doctor


 I did not get yours of the
 5 till yesterday at evening.
 I have prepared the Expl. [Explanations] of the 
 plates. Sprague is finishing
 the last Abronia, which he has 
 been giving him a world of trouble 
 to find out about the stamens,
 &c.


 After what you write 
 about the work the printers 
 make, I think there 
 is no call to write out a 
 character of Abronica fragrans. 
 I think I mentioned in the 
 mss. [manuscript] I sent that it differs from 
 A. [Abronia] mellifera mainly in the very 
 broad & scarious leaves of the involucre,
 and in the less winged fruit. 
 What I have said (enclosed) of 
 the Penstemon heterandrum [heterander] touches 
 all the points, and I hope will
        