382 



RECORDS. 



Fig. 3. — Relationsof the chromosomes ; formation and distribution of protoplas- 

 mic stuffs in later stages. A, union of the germ nuclei (each assumed to have four 

 chromosomes). B, C, division of the chromosomes, with equal distribution of the 

 paternal ( $ ) and maternal ( 9 ) products. D, scheme of nucleus at any later 

 stage, with four paternal and four maternal chromosomes (corresponding or homol- 

 ogous chromosomes connected by dotted lines). E, actual outline (after Mead) of 

 egg of Amphitritc consisting of upwards of 64 cells (nuclei schematized). Ento- 

 blast-cells unshaded, primary mesoblast cross-hatched, trochoblasts (ciliated jells) 

 dotted, cells of ventral plate (ventral nervous system, etc.) black; the other cells 

 belong to the ectoblast. 



