390 METHODS AND FORMULAS DS 21.13-DS 21.14 



21.13 Verhoeff 1908 11006, 50:876 



REAGENTS REQUIRED: A. abs. alc. 60, hematoxylin 3, 10% ferric chloride 0.25, ADS 12.2 



Lugol (1905) 25; B. 2% ferric chloride 

 PREPARATION OF A: Dissolve hematoxylin in alc. Add ferric chloride. Filter. Add iodine 



solution to filtrate. 

 method: [sections] -^ water — > A, till black, 10-20 mins. -^ B, till differentiated, 2-10 



sees. -^ water, thorough wash — » 95% alc, till no more iodine comes away — » balsam, 



via usual reagents 

 result: elastic fibers, black. 

 note: Verhoeff (loc. cit.) recommends a 2% solution of eosin Y if counterstaining is 



required. 



21.13 Volkman and Strauss 1934 see DS 21.13 Weigert 1898 (note) and DS 13.7 Volkman 

 and Strauss 1934 



21.13 Weigert 1898 23681, 9 :290 



FORMULA OF DRY STOCK: Water 100, magenta 1, resorcinol 2, 30% ferric chloride 12.5 



preparation OF DRY STOCK: as French 1929 



WORKING solution: 95% alc. 100, dry stock 0.75, hydrochloric acid 2 



preparation of working solution: as French 1929 



method: [sections] -^ 95% alc. -^ stain, 2-24 hrs. —* 95% alc, tUl no more color comes 

 away -^ balsam, via usual reagents 



result: elastic fibers, blue black. 



note: Fischer {test. Schmorl 1928, 167) suggested the substitution of safranin or Bis- 

 marck brown for magenta and designated such solution by the suffix -elin. Hence, the 

 names fuchselin (with magenta), vesuvelin (with Bismarck brown) and safranelin 

 which add confusion to the literature. Volkman and Strauss 1934 use crystal violet. 



21.13 Unna see DS 12.216 Unna (1928) 



21.13 Zieler see DS 23.221 Zieler 1903 



21.14 STAINS FOE CHITIN 



The few methods recorded in this section are not intended for the general staining ot 

 sections of arthropods, for which purpose any of the better-known triple stains can be 

 employed. Bethe 1895 is based on a standard microchemical test for chitin and is designed 

 principally to assist in the reconstruction from serial sections of portions of the endoskeleton 

 which cannot well be made out in cleared specimens. The formulas of Gage, Racovitza, and 

 Smith are intended only for wholemounts and should be used in those cases in which a valu- 

 able specimen has, through carelessness, been left in potash for so long that it has become 

 too transparent. Such specimens are difficult to stain and the formula of Smith is invaluable 

 for this purpose. 



21.14 Bethe 1895 23831, 8:544 



reagents required: A. water 100, aniline hydrochloride 10, hydrochloric acid 1; B. 



7.5% potassium dichromate 

 method: [sections] -^ water —* a, 5 mins. —» water, quick rinse —» B, 1 min. — > tap 



water, tUl color changes from green to blue — > balsam, via acetone 

 recommended for: demonstration of chitin in sections. 



21.14 Chatton 1920 see DS 12.212 Chatton 1920 



21.14 Gage 1919 7871,30:142 



formula: water 100, hydrochloric acid 1, acid fuchsin 0.2 

 RECOMMENDED FOR: potash-cleared chitinous skeletons. 



21.14 Nuttall 1908 see DS 12.16 Nuttall 1908 



21.14 Racovitza test. 1942 Langeron Langeron 1942, 924 



REAGENTS REQUIRED: A. 1% pyrogalHc acid; B. 0.5% hydrochloric acid 

 method: [potash-cleared exoskeletons of arthropods] —» water, thorough wash— > A, 



3^ to 1 hr. -^70% alc, in strong light, till darkened -> B, if differentiation required 



—> balsam, via usual reagents 

 note: Vaulx 1920 (5401, 65:214) mordants for 15 minutes in a sat. sol. ferric sulphate 



before this treatment. 



