6 
Transfer to 35 per cent alcohol, 2 minutes. 
Transfer to distilled water, 3 to 5 minutes. 
Transfer to second bath of distilled water to get rid of all traces of alcohol, 5 minutes. 
Transfer the sections to dilute Delafield’s hematoxylin. I usually employ 1 part of the 
stock solution of hematoxylin to 9 parts distilled water. The duration of the stamimg will 
vary with different objects. It is well to remove, wash, and examine sections at intervals, and 
when the stain is found to be that desired the next step can be taken. By the use of the dilute 
stain overstaining is prevented. In the case of celloidin sections only the tissues of the sectioned 
object are stained; the celloidin matrix is not stained. 
Wash sections in distilled water. 
Transfer successively to 35, 50, and 70 per cent alcohols, leaving the sections from 2 to 3 
minutes in each. . 
Transfer a few sections at a time to 95 per cent alcohol in which they may remain from 
3 to 5 minutes. 
Transfer them to carbol-xylol. This is a mixture of equal parts carbolic acid and xylol. 
In making it take a dry test tube, in it place enough crystals of pure carbolic acid to fill it about 
one-fourth of its length, melt these over a flame, allow the resulting liquid to cool, and then 
add an equal volume of xylol. Do not, however, bring the xylol near the flame. Each section 
should be allowed to remain in the carbol-xylol at least 10 minutes; a longer time will not 
injure them. The object of placing the sections in the carbol-xylol is to clear them. 
(It will be observed that in the above process we pass directly from 95 per cent alcohol 
into our clearing fluid. This is because absolute alcohol dissolves celloidin and would thereby 
free the sections from the matrix which holds them together. Carbol-xylol is used because 
it clears objects which have not been completely dehydrated.) 
Transfer the section to a slide; take up the excess of carbol-xylol by the use of a piece of 
filter paper, but do not let the section get entirely dry. Add a drop of Canada balsam, place a 
cover glass over it in the usual way and the mount is ready for study. 
DECIDUOUS FRUIT INSECT INVESTIGATIONS. 
A. L. Quaintance, In Charge. 
Mr. B. R. Leach, who has been on furlough, attending Cornell University, since December 1, 
1914, resumed his dies February 1, 1915. 
In cooperation with Prof. C. P. Gillette, director and entomologist of the Colordde Agri- 
cultural Experiment Station, a laboratory has been established in the Grand Junction district 
of Colorado, where particitor attention will be given to a study of the biology of the codling 
moth in that region. Extensive orchard spraying experiments are also planned. The codling 
moth in the Grand Valley has been for some years unusually destructive, and the methods ot 
control successful in other regions do not here furnish satisfactory protection from its injuries. 
Mr. E. H. Siegler, who has been attached to the Benton Harbor, Mich., laboratory, will 
be in immediate charge of the bureau work in the Grand Junction district. 
The laboratory which has been in existence at Winthrop, Me., during the past two years 
will be discontinued, since the codling moth life-history studies in that region have now been 
completed and results prepared for publication. 
Mr. F. L. Simanton will be transferred to the laboratory at Benton Harbor, Mich. 
