80 THE AMERICAN ARBACIA 



Variation in size by one investigator is shown by: 



Goldforb's (1935a) figures for 1,000 eggs from 25 females: 68.3 // 



to 77.4 [JL diameter. 



Shapiro's (1935 c) figures for eggs measured through summer of 



1934: 64 [X to 81 [i. diameter. 



Variation in size has also been studied by Glaser (1914a, 1924) 



and by R, S. Lillie (1916 a), 

 Variation is great for diflferent females but is quite small for the eggs 

 of one female, as noted by many observers and studied especially by 

 Goldforb (1935 a). 



g. Aberrant Sized Eggs and Nuclei 



Aberrant sized eggs and nuclei. Occur in some batches of normal eggs; 

 are uniform in size with no gradations in any one batch (E. B. Harvey) . 



1. Giant egg with giant nucleus. Egg D. 91 fx. Nucleus 14 y., (1939) ; 

 in 1% of eggs; normal development. Egg D. 960,, Nucleus 14.4 [x; 

 in a few eggs (1950). 



2. Normal egg with giant nucleus. Egg D. 72 [i, Nucleus 17 [x; in 

 1% of eggs; normal development (1940). Egg D. 71 [x, Nucleus 29 [x; 

 in .01% of eggs; abnormal development (1939). 



3. Small egg with giant nucleus. Egg D. 57.6 [x, Nucleus 16.5 [x; 

 normal cleavage, blastulae, no plutei (1940). 



4. Small egg with normal nucleus. Egg D. 50 jx. Nucleus 11.5JX 

 (1940). 



5. Normal egg with 2 nuclei, same volume together as a normal 

 nucleus (1940). 



6. Immature egg with two germinal vesicles (1943). 



