SPERMATOGENESIS OF ASCARIS 447 
3. In the young spermatocyte the karyochondria pass through 
the nuclear membrane into the cytoplasm, where they form the 
‘refringent granules.’ These at once begin the elaboration or 
secretion of yolk within themselves, and so become the ‘refrin- 
gent vesicles.’ These then fuse to form the ‘refractive body,’ as 
the spermatid transforms into the spermatozoon. This trans- 
formation takes place entirely within the vas deferens. 
4, The refractive body is purely a food supply for the use of 
the speratozoon, and frequently it is entirely consumed before 
the spermatozoon enters the egg. It therefore plays no part in 
fertilization; hence, the only function of the karyochondria in 
Ascaris is to form yolk. 
5. The plastochondria are, like the plastosome, merely residua, 
and show negative behavior wherever they occur. While many 
are retained by the spermatozoon, many are lost by the spermatid. 
6. Through the use of a single basic or nuclear stain, these 
two kinds of cytoplasmic inclusions have been confused. The 
simplest ‘double stains’ distinguish them clearly. 
LITERATURE CITED 
AuttmMaNn, R. 1896 Uber die Granula und intergranular Substanzen. Arch. Anat. 
und Physiol. 
AUERBACH, L. 1894 Spermatologische Mitteilungen. 72 Jahr. Schles. Ges. vat- 
- erl. Kultur. 
BaurzEr, F. 1910 Uber die Beziehung zwischen dem Chromatin und der Ent- 
wicklung. Arch. f. Zellf., Bd. 5. 
Benpa, C. 1903 Die Mitochondria. Ergeb. der Anat. und Entw., Bd. 12. 
Bourn, P. 1905 Ergastoplasm, pseudochromosomes, et mitochondria, etc. Arch. 
Zool. Exper., Bd. 3. 
Boveri, T. 1888 Die Befruchtung und Teilung des Eies von Ascaris megalo- 
cephala. Zellen Studien. Jena. 
1899 Die Entwicklung von Ascaris megalocephala, etc. Jena. 
Braver, A. 1893 Zur Kentniss der Spermatogenese von Ascaris megalocephala. 
Arch. mikr. Anat., Bd. 42. 
Broman, I. 1907 Uber Bau und Entwicklung der Spermien von Rana fusca. 
Arch. mikr. Anat., Bd. 70. 
Cuampy, C. 1909 Mitochondria et corps chromatoides des spermatogonies des 
Anoures. Compt. r. Soc. Biol., T. 66. 
Conxkuin, E. G. 1905 The organization and cell lineage of the Ascidian egg. 
Jour. Acad. Nat. Sci., vol. 13. 
DuszerG, J. 1907 Der mitochondrial Apparat in den Zellen der Wirbeltiere 
und Wirbellosen. Arch. mikr. Anat., Bd. 71. 
