1884. ] Microscopy and Histology. 959 
MASS FOR ORDINARY INJECTIONS, 
Dry starch (“laundry ”’ is good)... ..ceeeeeeeee eesseesseees 1 vol. 
r cent aqueous solution of chloral hydrate.........ses-.+0 es 
Dever cent BICUHON. fo. Scie ec eee La EES s adie 
Color. i 
Since almost any animal injected may afford some organ worth 
preserving, it seems better to employ permanent colors for tinge- 
ing the mass. Among those which are available, probably ver- 
milion, red lead, ultramarine, chrome orange, yellow, or green, 
are preferable. 
PREPARATION OF THE COLOR. 
MM eae CU Ce eck Succ h cel ca ceb ret le T ies t vol. 
NEO, Seis Vee UU E avi o's pees cs E EA E ie 
See aa n AEE dieid uk bs oa bic ARH el ee P S Lets 
To avoid lumps, which would clog the cannula, or small ves- 
sels, the color is thoroughly ground with the liquid in a mortar. 
It is stored in a well-stoppered bottle, and is prepared for use 
simply by shaking. 
Special Mass——For the injection of brains, and, perhaps, for 
other rapidly perishing specimens, it seems best, as suggested by 
Professor Wilder, to use strong preservatives in preparing the mass: 
Corn starch (that used for food): ¢ eers A eo ek Ok 
per cent aqueous solution of chloral hydrate ........--++++++++ E 
Os P cent atoh a Oca see oes ibe sabes wees eee ees 4% 
OM. Sales cia Vis aegis side vin is heels chan Ses OE ae p s 
dation of the liquid. In this case some mass containing double 
= ordinary amount of starch can be advantageously injected in 
© hours or longer after the first injection. 
* The chloral and alcohol prevent fermentation in the mass when it is kept in 
Stock; the alcohol also acai the fluidity and likewise the mcre rapid hardening 
im the vessels; both, of course, act as a preservative upon the animal injected. 
