gametoCtENesis of saccocireus 45 



62. Weigl, R.— " Vergleichend-zytologische Untersuchungen iiber den 



Golgi-Kopschen Apparat ", ' Bull. I'Acad. Scien. Cracovie ', 1912. 



63. Wilson, E. B.— " On Cleavage and Mosaic Work ", ' Arch. f. Ent.- 



Mech.', vol. 3, 1896. 

 64. " Experimental Studies in Germinal Localization ", ' Journ. 



Exp. Zool.', vol. 1, 1904. 

 65. — ' The Cell ', University Biological Series, 1919. 



18. EXPLANATION OF PLATES 1-4. 

 Illustrating Professor J. Bronte Gatenby's Paper 



ON THE GaMETOGENESIS OF SaCCOCIRRUS. 

 Explanation of Lettering. 

 AS, acrosome. ar, archoplasm or centrosphere. CH, chromosomes. 

 CHO, vitelline membrane, cl, cortical lamellae of egg. ga, Golgi apparatus 

 (' Nebenkern '), Golgi body or element, gax, body supposed to be a part 

 of the Golgi apparatus. GX, body believed to be forming the acrosome. 

 M, mitochondria, mm, macromitosome or forming middle-piece (mito- 

 chondria) of sperm-tail. N, nucleiis. nl, nucleolus, or fragments of 

 latter forming nucleolar deutoplasm. nlx, nucleolar bodies homologous 

 with the true nucleolar deutoplasm of egg. nlv, vacuoles around the 

 nucleolar extrusions, sb, spindle-bridge, spt, sperm-tail, spz, sperma- 

 tozoa, sp, sperm inside young oocyte, v, vacuoles in ground protoplasm 

 of oocyte, x, bodies believed to form a part of the skeleton of the sperm- 

 tail, on each side of the macromitosomal (mitochondrial) spheres, xn, 

 nuclear-like bodies sometimes found in oocytes, possibly secondary 

 nuclei, xy, bodies near asters, possibly part of the Golgi apparatus. 

 Y, yolk-spheres, yc, yolk-cell or nurse-cell. 



Scale of Figures. — On PI, 1, all figures, except number 6, are drawn 

 to the scale indicated in the middle of the plate. The scale for fig. 6 

 is near the drawing. 



On PI. 2, all figures, excepting 17 and 18, are drawn to the scale in the 

 middle of the plate, the scale for figs. 17 and 18 being near by. 



All figures on PI. 3 are drawn to the scale on the right-hand side. On PI. 4, 

 all figures, excepting number 34, are drawn to the scale given below fig. 29, 



Techniques Used .— m.k., Mann-Kopsch osmium tetroxide method. 

 CH.K., Champy-Kull chrome-osmium acid f uchsin toluidin blue and aurantia 

 method, d.f., Da Fano's cobalt nitrate formol-silver nitrate method. 



Plate 1. 

 Fig. 1. — Full-grown spermatocyte and part of nurse- or yolk-cell on 

 left. In the spermatocyte the Golgi apparatus (ga), the mitochondria (m), 

 and the group of yolk-spheres (y) are to be seen. The nurse-cell contains 



