730 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Orthoptera to the slide is easily overcome by sticking them down with 

 •0" 25-0 *5 p.c. solution of photoxylin in equal parts of alcohol and ether ; 

 this does not interfere in any way with the further manipulation. 



The fixatives mostly used were Flemming's and Hermann's fluids, 

 but excellent results were obtained from formalin-chrom-acetic acid and 

 formalin-alcohol-acetic acid ; in the formalin mixtures the material was 

 immersed for 6-8 hours. 



The sections, which were from 3-20 /* thick, were stained with 

 Heidenhain's iron-hgematoxylin or with Ehrlich's alcohol-hasmatoxylin. 



Studying the Histology of the Lungs of Domesticated Animals.* 

 J. Miiller fixed the lungs with absolute alcohol, or with 4 p.c. formalin, 

 by passing these fluids into the trachea. For alcohol 48 hours sufficed, 

 while formalin required 4 days or longer. Cubical blocks with sides 

 from • 5-1 ' 2 cm. were cut out of the fixed tissue. The pieces fixed in 

 formalin were dehydrated in upgraded alcohols. The material was then 

 cleared in xylol or cedar-oil, and afterwards imbedded in paraffin, the 

 latter process taking several days in order to get rid of all the air. 

 Sections from 4-30 /x. were made, and were stained with hseniatoxylin, 

 haernalum, borax-carmin, and lithium-carmin. The contrast-stains were 

 eosin, fuchsin, or Hansen's picric-acid-fuchsin. The elastic fibres were 

 picked out by Weigert's method. For the mucous glands, thionin, 

 mucicarmin, niuchaematin, and methylen-blue were used. 



For corrosion preparations Wickersheim's alloy (lead 32, zinc 16, 

 bismuth 60, cadmium 12, mercury 10 parts) was employed. The lique- 

 fied metal was injected through the trachea, or a large bronchus, after 

 the lung had been thoroughly warmed by immersion in water at 65°. 

 The maceration was effected by means of 10 p.c. caustic potash. 



For demonstrating the respiratory epithelia, the pulmonary tissue 

 was filled with 0*2 p.c. silver nitrate, and afterwards hardened in 

 upgraded alcohols, the material being kept in the dark the while. After 

 the paraffin sections had been mounted in balsam or in glycerin, they 

 were exposed to sunlight. 



For demonstrating the pores in the alveolar walls, living animals 

 were killed by confining them in an atmosphere of carbonic acid. This 

 made the lungs perfectly atelectatic. They were then injected through 

 the trachea with an aqueous solution of Berlin-blue and gelatin under 

 very slight pressure. 



Studying the Pollen-tube in Houstonia coerulea.f — 0. A. Matthew- 

 son fixed both old and young flowers in Flemming's fluid, chrom-acetic 

 acid, and alcohol-acetic solution. The Flemming triple stain was used 

 for the first two fixatives. 



The tissue fixed in alcohol-acetic solution was stained with iron- 

 alum-hgematoxylin and Bismarck-brown. The latter method gave the 

 best results. The sections were all 10 /* thick. 



Studying the Cytology of the Entomophthoracese.f — L. W. Riddle 

 Jxed most of the material in 0*75 p.c. chrom-acetic acid, which gave 



* Archiv Mikrosk. Anat. u. Entwickl., lxix. (1906) pp. 1-61 (1 pi.). 



t Bull. Torrey Bot. Club, xxxiii. (1906) pp. 487-93. 



% Proc. Amer. Acad. Arts and Sci., xlii. (1906) pp. 177-97 (3 pis.). 



