. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HEMOCYTES AND TANNING 769 when more fully formed and hardened, it became acidophilic, as if basic substances had penetrated. The epicuticle which covered the fully tanned exocuticle exhibited basophilia. However, at ecdysis, the epicuticle became acidophilic. It contained aldehydes by the black Bauer and black periodic methods; sudanophilia was absent. By PAS staining, the new exocuticle contained 1,2-glycols variably during proec- dysis, ecdysis, and late postecdysis. This reaction became abolished by acetylation, but it wa
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HEMOCYTES AND TANNING 769 when more fully formed and hardened, it became acidophilic, as if basic substances had penetrated. The epicuticle which covered the fully tanned exocuticle exhibited basophilia. However, at ecdysis, the epicuticle became acidophilic. It contained aldehydes by the black Bauer and black periodic methods; sudanophilia was absent. By PAS staining, the new exocuticle contained 1,2-glycols variably during proec- dysis, ecdysis, and late postecdysis. This reaction became abolished by acetylation, but it was not restored by deacetylation. Exo- and endocuticle did not react early in postecdysis. The reaction was negative in intermolt crabs. No glycogen, aldehydes, nor lipids were detected. Using various diazonium salts, the cyclic appearance of aromatic protein end- groups was detected within the cuticle's protein matrix. The exocuticle layer azo- coupled mildly during proecdysis and ecdysis indicating proteins exist in low con- centration. The azo-coupling of the cuticle proteins intensified during early postecdysis. During late postecdysis, more aromatic end groups appeared in the outermost exo- cuticle than in the newer endocuticle layer. The epicuticle did not azo-couple. Sub- sequent extraction in weak HC1 failed to change the results. Diphenols in cuticle. The reaction of the cuticle to the DAS-AzA showed variations in the staining for phenols throughout the molting cycle. At intermolt and proecdysis, the fully-formed and hardened (quinonized) procuticle did not azo-couple. In contrast, phenols penetrated the soft exocuticle at ecdysis and azo-coupled intensely (Fig. 7A). The azo-coupling capacity of phenols in the exocuticle decreased as tanning progressed during early postecdysis; by 10 hours postecdysis only small amounts could be detected. By late postecdysis, the new endocuticle still reacted moderately for phenols. However, its azo-coupling capacity continued to decrea
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
