
          68

Cf. Report of Cyrus Thomas, St. Entomologist of Ill. on Plant
Lice, 1877 or 8.

Prof. T. J. Burrill says (Tr. Ill. St. Hort. Soc. 1880 p. 165)
in a paper on "Pear and Apple Tree Blight" that:

"So far as my examination show, this is also true of the
peach yellows, [i.e. that roots do not blight].  The roots sent
me were certainly free from disease, while the bark and pith of
the parts above ground were full of bacteria."

"Pear blight and Peach Yellow" by T. J. Burrill, pp. 46-49,
Tr. Ill. St. Hort. Soc., 1883.

Prof. B. says: "Three distinct lots of specimens were received
[from Detroit and So. Haven, Mich.], and after a careful examination 
of them it seemed to me that the conclusion was warrantable
that the cause of the well-known contagious [contagions] was an organism
found in the affected tissues, not very unlike that of blight in
the pear.  This conclusion appeared in public print, perhaps prematurely."
x x

Prof. B. follows with some excellent statements, and disclaims
any definite opinion on this subject.

"I know some [peach] trees now that are 40 years old."--Mr.
Augur, of Conn. p. 200, 13th An. Report N. J. Bd of Agric. 1885.
[Ask him where they are].

"In pear blight it is easy to discover the bacteria.  Any one
        