No. 1. — Spermatogenesis of Caloptenus femur-riibrum and Cicada 

 tibiccn} By E. V. Wilcox. 



The following observations were made on the testes of Cicada and 

 Caloptenus. Only three male Cicadas were at my disposal, but of 

 Caloptenus I examined more than twenty individuals. The Cicadte 

 were killed immediately after leaving the pupal case, and had been pre- 

 served a number of years. The Calopteni were taken in August and 

 September, 1893. 



The testes of Cicada were killed in Mtiller's fluid ; those of Caloptenus 

 either in hot water, in hot corrosive sublimate, in cold corrosive subli- 

 mate, or in chrom-osmic-acetic mixture. Some of the testicular folli- 

 cles of Cicada were stained in Grenacher's alcoholic borax carmine, 

 others according to Bizzozero's modification of Gram's method. The 

 follicles were stained in toto in safranin (50% alcohol) 24 hours, sec- 

 tioned, stained 3 minutes in gentian-violet, washed 5 minutes in a solu- 

 tion of potassic iodide, then treated alternately with alcohol and chromic 

 acid (0.1%). But better results were obtained by double staining with 

 safranin and victoria-green. Crystals of the latter were dissolved in 

 absolute alcohol, or in clove oil. The sections were first stained in 

 safranin (10-15 minutes), the excess of stain being quickly washed off 

 in 90% alcohol, and then in a very strong solution of victoria-green in 

 absolute alcohol for 1 to 2 minutes. Staining and dehydrating were 

 thus accomplished at the same time. Excess of green was washed out 

 with absolute alcohol. Sections were cleared in clove oil. When a 

 clove-oil solution of the green was used, the sections were dehydrated 

 before staining in the green. The method with the absolute-alcohol 

 solution gave the better results, and was more easily managed. 



The Caloptenus material was all stained on the slide. The methods 

 used were either safranin and victoria-green, as just described, Henne- 

 guy's ('91) potassic permanganate and safranin, or Heidenhain's ('92) 

 iron-hsematoxylin. The method with safranin and victoria-green gave 

 good results. Cytoplasm and achromatic nuclear parts were stained 

 green, the chromosomes, nucleolus, and centrosomes red. If the green 



1 Contributions from the Zoological Laboratory of the Museum of Comparative 

 Zoology at Harvard College, under the direction of E. L. Mark, No. XLVII. 



VOL. XXVII. — NO. 1. 



