July, 1922] 
CLELAND — OENOTHERA FRANCISCANA 
411 
10. The longitudinal split in the daughter chromosomes preparatory to 
the homoeotypic division does not appear until late interkinesis. During 
interkinesis, the individual chromosomes remain clearly visible, being 
attached in only the most meager way. 
11. The homoeotypic division is in no respect unusual and is followed 
by the simultaneous cutting in of walls to form the four spores of the tetrad. 
12. The nucleus of each spore passes into a resting condition in which 
all trace of the individual chromosomes is lost. This process is easily 
followed, and it is clear that no splitting of the chromosomes into two 
threads takes place, as has been described in the telophase of some plants. 
13. The chromosomes in this plant are arranged telosynaptically, and 
form a univalent spireme during prophase of the heterotypic mitosis. 
14. The reduction processes in Oenothera franciscana, which is geneti- 
cally a very stable species, are extremely regular and typical, in striking 
contrast with what is found to be the case in the less stable species of 
the genus, but in agreement with the condition which has been found 
in one of the other stable species, Oe. grandiflora. 
GoucHER College 
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