OVARY AND OVARIAN EGG OF ANOPHELES 495 
it should now degenerate. This it does, as we have seen, by 
continuing to branch till the final branches merge into the 
reticulum of the cytoplasm, when nutrition is completed. 
III. Discussion concerning the Oocyte Nucleus 
and Nutrition of the Oocyte in A. Maculi- 
pennis. } 
I have unfortunately not found it possible to examine the 
whole of the literature dealing with the nutrition of insect 
eggs, but, in the literature I have consulted, I have not 
discovered a case in which the mechanism of nutrition is to my 
mind as clearly demonstrated as it is in the developing egg- 
follicle of A. maculipennis. I do not believe, however, 
that the insect under consideration is unique in having this 
particular mechanism of nutrition. From several series of 
sections which I cut of the closely allied insect Theobaldia 
annulata, I am convinced that the same mechanism is 
present here. Also Soyer (28) makes a short reference to the 
nucleus of the developing oocyte of a Staphylinid, and from 
his description it would appear closely to resemble that of 
A. maculipennis. He remarks, ‘ Le noyau, trés irrégulier 
déja a ses phases les plus jeunes, se ramifie et se déchire en 
une multitude de franges dans toute l’étendue du vitellus. 
Cette ramification finit par étre poussée si loin qu’on n’a plus 
sous les yeux qu’une sorte de long filament avee quelques 
branches latérales, a peine visibles, dont les extrémités se 
ramifient et se perdent entre les vésicules lécithiques qui 
emplissent & ce moment la masse ovulaire’. According to 
Korschelt (18) Stuhlmann has observed the branching of the 
nucleus throughout almost the entire oocyte of Necrophorus 
vespillo and of Silpha sp. 
Branched nuclei are by no means uncommon, particularly 
in insects. They are commonly found in nurse-cells, gland- 
cells, fat body-cells, and the cells of Malpighian tubules, in all 
of which cases they appear to have some relation to the secretory 
activities of the cells. Thus in many gland-cells the nucleus 
is only branched during the period of secretion, In only two 
