1915] BARTLETT—MASS MUTATION 437 
but no progenies have yet been grown or chromosome counts made, 
except in the case of one plant, belonging to the mass mutant strain. 
Lexmgior? LE 5 Far th 
Co Oe 
Fic. 5.—Progeny of Lexington E-5, pan 11 (part of culture 5; see table II); 
the pan contains 49 plants, which were classified (most of them at maturity) as follows: 
Row I 2 3 4 5 6 | 7 
5 Ee ete Pe ..| setacea | gigas (no. typica (no, | setacea setacea | setacea setacea 
238; see 239; see 
fig. 15) fig, 15) 
eee ee ares on setacea | setacea setacea setacea setacea | setacea setacea 
Rises res setacea | typica typica setacea setacea | typica setacea 
Mit kietweed, setacea | setacea setacea formosa setacea | revoluta setacea 
{no. 206; 
fig. 12) 
ae aN ti setacea | setacea setacea setacea setacea | formosa revoluta 
(no. 164; (no. 207; (no. 172; 
see fig. 7) see fig. 12) see fig. 8) 
en ‘ setacea | setacea albicans setacea setacea | revoluta setacea 
Tee beh aces typica | setacea setacea setacea setacea | setacea setacea 
