202 First. Maturation Spindle of Allolobopliora Foeticla 



honey-comb structure and at the spindle stage there are fewer alveoli and 

 those present are much smaller. The increase in the amount of substance 

 between the inner and outer membranes of the egg and decrease in the 

 number and size of the alveoli, suggest that the former may be increased 

 at the expense of the latter, but we have no proof of this. 



Osmopliih Granules. — Typical osmophile granules in the cytoplasm of 

 nornuil eggs found in the receptaculum ovoriim are demonstrated in the 

 unstained sections of Photos. 68 and 69, Plate IV. A comparison of 

 these sections with the ovarian eggs of Plate 42 of an earlier paper 

 (1901) shows a diminution in the amount of osmophile substance in 

 these older oocytes. In the above mentioned paper we noted a decrease 

 in the amount of osmophile substance between the ovarian and the 

 cocoon eggs and suggested that the storing. of the osmophile substance in 

 the ovarian egg must be for the use of the egg from the time it leaves 

 the ovary until it is supplied with the nutritive albumen of the cocoon, 

 i. e., during the prophases of the first maturation spindle. This supposi- 

 tion seems confirmed now that w^e know these processes go on very 

 slowly in the receptacula ovorum and that the osmophile substance 

 gradually diminishes in amount during this period. 



We first demonstrated these osmophile (deutoplasmic) granules in 

 1898, and in subsequent papers have presented additional data. "\Ye have 

 shown that they are not dissolved out of the cell by either turpentine or 

 xylol, but that after staining they are as a rule invisible, having lost all 

 trace of the blackening caused by the osmic acid. This also fades in 

 unstained eggs that have been kept for a long time in paraffine or 

 mounted in balsam. If a section is photographed before staining, Plate 

 IV, Photos. 68 and 69, and then stained in iron hoematoxylin the granules 

 are indistinguishable even with a 3 mm. lens, but if the section is com- 

 pared with a photograph of the unstained preparation that shows exactly 

 where to look for each granule, they can be identified as clear, colorless 

 bodies that would entirely escape observation without the photograph 

 as a guide. 



Centriole and Spindle. — In this paper we shall adopt Boveri's term 

 centriole for the small central granule of the asters for which in an 

 earlier paper we retained the old term centrosome. We drop the term 

 centrosome for this granule not because we find a second body in the 

 asters of Allolohophora which answers to the centrosome of Boveri and 

 others, but to avoid the confusion of retaining an old term which implies 

 a structure and accompanying complicated changes Avhich we have not 

 found in this egg. 



The centrioles destined for the two poles of the first maturation 



