444 A. J. NICHOLSON 
probably also exists in Necrophorus yespillo and 
Silpha sp. 
23. The branching nucleus is almost entirely the product 
of the nucleolus. 
24. The branching nucleus is morphologically and physiologi- 
‘ally comparable to the Corpuscles of Balbiani of other animals. 
25. The germinal portion of the nucleus, the ‘ chromatin 
residue ’, is the product of the condensation of the spireme 
threads. 
26. The ‘ chromatin residue’ becomes invisible for a short 
period and reappears after oviposition as the segmentation 
nucleus. 
27. The chromatin of the active nurse-cells consists of 
minute bars situated on a much convoluted band of linin. 
28. Degeneration of a certain number of egg-follicles is 
normal during the development of the ovary. 
29. Sporozoa are frequently found in the eggs, often com- 
pletely replacing the whole of the yolk. 
List or LirERATURE. 
1. van Bambeke.—“‘ Recherches sur l’odcyte de Pholcus phalan- 
gioides”’, ‘ Arch. de Biol.’, t. 15, 1897. 
2. Christophers, 8. R.—‘‘ The Anatomy and Histology of the Adult 
Female Mosquito’, ‘Roy. §$oc., Reports to the Malaria Com- 
mittee ’, Fourth Series, London, 1901. 
3. —— “The Development of the Egg-follicle in Anophelines ”, ‘ Palud- 
ism’, Simla, pt. 2, 1911. 
4, Chubb, Gilbert C.—‘‘ The Growth of the Oocyte in Antedon”, 
‘Phil. Trans. of the Roy. Soc. of London ’, Series B, vol. 198, 1906. 
5. Doncaster, L.— An Introduction to the Study of Cytology’, Cam- 
bridge, 1920. 
6. Dublin, L. J.—‘‘ On the Nucleoli in the Somatic and Germ Cells of 
Pedicellina americana ”’, ‘ Biol. Bull.’, vol. 8, 1905. 
7. Gatenby, J. Bronté.—“ The Identification of Intracellular Structures ”’, 
‘Journ. Roy. Micr. Soce.’, 1919. 
8. —— “The Cytoplasmic Inclusions of Germ Cells”, pt. iv, ‘ Quart. 
Journ. Micr. Sci.’, vol. 64, pt. 2, 1920. 
9. Gross, J.——“‘ Untersuchungen iiber die Histologie des Insecten- 
ovariums ”’, ‘ Zool. Jahrb. Jena’, vol. 18, Heft 1, 1903. 
