97 



mens, particularly of the lower orders of plants, 

 it would be impossible to present an absolutely 

 complete list, and perhaps with even the greatest 

 facilities no one has succeeded in so doing for 

 any region. 



Almost the only extended collection of dried 

 specimens of county plants were those of the 

 late Mr. Oakes, so that there really exists no 

 very great foundation upon which to build, other 

 than the herbarium recently collected, and the 

 writings of the more reliable among the earlier 

 botanists, who for nearly a century have now 

 and then appeared upon the scene. 



Of the plants enumerated, almost all are rep- 

 resented in the herbarium of the Peabody Acad- 

 emy of Science at Salem, and where the species 

 has not been collected and its occurrence is only 

 known by the testimony of some writer, it is so 

 stated in the list. 



Several errors have been detected in early 

 local lists and corrected, and such notes added 

 to the paper as seem of interest locally or 

 otherwise. 



The writer would express his indebtedness to 

 Prof. Asa Gray, Prof. G. L. Goodale and Prof. 

 Sereno Watson, for their numerous kindnesses 

 and assistance rendered him during the past five 

 years while preparing this flora, and also to 

 Messrs. Edwin and Charles E. Faxon for their 

 kindness in revising the final proofs. 



ESSEX IXST. BULLETIN, VOL. XII. 7 



