262 SUMMARY OF CURRENT RESEARCHES RELATING TO 



(2) Preparing: Objects. ' 



Preparing Suprarenal Bodies of Guinea-Pig's.* — F. Fuhrmann, 

 who studied the liner structure of the suprarenal bodies of guinea-pigs, 

 found that the best fixatives were Zenker's fluid, Midler's fluid, and 

 formalin in proportion of 9-1 ; 4 p.c. formalin and saturated subli- 

 mate solution in ' 75 p.c. salt solution. For cell examination Hermann's 

 platinum- chloride- osmic- acetic acid mixture, or Flemming's chrorn- 

 osmium-acetic acid mixture, gave excellent results, provided the glands 

 were cut up into slices of about 2 mm. thick. After fixation, the pieces 

 were washed in running water, and then hardened in alcohol. Paraffin 

 and celloidin sections were made. For the latter, solutions of celloidin 

 dissolved in methyl-alcohol were used, and the pieces were transferred 

 from ethyl-alcohol to the thinnest, and afterwards passed through the 

 thicker sections. The celloidin was hardened in 65 p.c. alcohol, and 

 was ready for cutting in about an hour. The sections were cleared with 

 origanum oil. One great advantage over the ether-alcohol method is 

 that the fat is much less dissolved out. 



The sections were stained by Benda's method — i. e. they were first 

 mordanted with sulphate of iron, and then treated with 1 p.c. aqueous 

 hasmatoxylin solution. They were afterwards differentiated in the freely 

 diluted mordant, or by van Gieson's method. Alizarin I., diluted with 

 5 parts of water, and with the addition of a few drops of calcium acetate, 

 is also recommended. In this solution the sections remain for 24 hours 

 at incubation temperature. Several other ordinary staining methods gave 

 good results. 



Bayon — Demonstration von Praparaten der normalen und pathologischen Schild- 

 driise. 



[Contains some remarks on the action of fixatives on the colloid substance of 

 the thyroid gland, and on the nature of the vacuoles.] 



SB. Pkys.-Med. Geselhch. Wurzburg, 1904, pp. 97-102. 



Zilliacus, W. — Die Ausbreitung der verschiedenen Epithelarten im menscblichen 

 Kehlkopfe und eine neue Methode dieselbe festzustellen. 



[Gives method for differentiating the different kinds of epithelial culls in 

 human larynx.] Anat. Anzeig., xxvi. (1905) pp. '25-30. 



(3) Cutting-, including- Imbedding- and Microtomes. 



Celloidin Method for Hard Plant Tissues.f — A. B. Plowman 

 describes the following celloidin method which was developed and per- 

 fected by E. C. Jeffrey. Wood should be cut up into cubic blocks, not 

 more than 1 c.cm., and in such a way that the faces represent the desired 

 plane of section. If dry, the material must be repeatedly boiled to 

 remove the air ; the vacuum pump should also be used. Living tissue 

 should be killed and fixed by immersion in the following mixture : — 

 Saturated solution of sublimate in ?>0 p.c. alcohol, 3 parts ; saturated 

 solution of picric acid in 30 p.c. alcohol, 1 part. After 24 hours the 

 fixed blocks are passed through 40, 50, 60, 70, 80 p.c. alcohol, the stay 



* Zeitschr. wiss. Zool., lxxviii. (1905) pp. 552-60 (2 pis.), 

 t Bot. Gazette, xxxvii. (1904) pp. 456-b'l. 



