1904] BRIEFER ARTICLES 383 
1883). A mixture of equal parts of glycerin and alcohol was recommended 
by StRASBURGER (Das botanische Practicum 1884, Pp. 79) for facilitating 
the cutting of woody tissues. EEycLEsHymMER (Amer. Naturalist 34: 354- 
357- 1892, and Jour. Roy. Micr. Soc. 1892: 563-565) describes a series of 
four grades of celloidin for infiltrating, chloroform for hardening, and a 
treatment with glycerin before cutting. In view of these facts, we do not 
doubt that others, who like ourselves have used STRASBURGER’S method 
for softening woody tissues, have continued to use the glycerin and alcohol 
mixture when dealing with material imbedded in celloidin. 
Mr. Prowman has certainly presented the subject in a very usable 
form, and in. perfecting the application of fluoric acid he has made it 
possible to obtain better sections of refractory tissues. In my ‘‘correction”’ 
Tintended merely to lodge an objection to the characterization of my account 
aS a second-hand presentation of Dr. JEFFREY’s methods. A study of 
LeE’s Vade Mecum and the references there cited indicates that Dr. JEFFREY, 
like myself, is deeply indebted to previous investigators—CuarLEs J. 
CHAMBERLAIN, 
IHAVE been permitted to read the proof of Dr. CHAMBERLAIN’s com- 
ment onmy letter. Matters have now resolved themselves into a difference 
of opinion between Dr. CHAMBERLAIN and myself as to what constitutes 
hovelty and improvement in celloidin technique. Iam very willing to 
allow the case to rest on the practical value of the method published by 
Mr, PLOWMAN.—E. C. JEFFREY. 
AN ABNORMAL AMBROSIA. 
(WITH THREE FIGURES) 
peal x Ambrosia artemisiaefolia that had been run over by a wagon 
condit: Y injured bore both staminate and pistillate flowers in an abnormal 
the ». The young shoots bearing the flowers arose vertically from 
ote and injured main stem. 
— gaia flowers of this injured plant appeared larger than the 
contained f © heads were scattered, forming a loose raceme, and each 
heads the “wer flowers than usual. In the center of the older flower 
While —. Was a group of buds that appeared to be vegetative (fig. 1); 
._ ounger heads contained vegetative buds only within the bracts 
é the heads, the flowers having been entirely replaced. Instead of 
enter (f Style the older staminate flowers bore vegetative buds in the 
fo The pollen of these flowers appears to have been arrested 
