a a SS ee 
234 Proceedings of the Royal Physical Society. 
SUMMARY. 
1. The same strobila may give rise to normal ephyre and to ephyre 
having more or less than the normal number of arms, and in particular 
cases there is abrupt discontinuity, for examen from a four-rayed 
form to a twelve-rayed form. 
2, The total number of ephyre produced from the twenty-seven pro- 
ductive strobile was 278, of which ninety (2.e. approximately 32 per 
cent.) showed major or minor abnormalities. Of these 25:18 per cent. 
showed variation from the normal number of arms. Compared with 
the relative percentages for adult forms, this shows that there is a 
slight tendency during growth to elimination of abnormal forms. 
This is borne out by the figures given previously as regards tenta- 
culocysts. 
3. The largest number of ephyre given off by one strobila was twenty- 
eight, the average production from an individual strobila being 
about ten; it is possible that some of the strobilee may have given off - 
some ephyre before being collected, and in this case the number 
would be slightly higher. 
+. Seventy-eight per cent. of the strobile produced ephyre at least some 
of which varied in some respects from each other and from the 
normal eight-rayed type, as compared with 22 per cent. of the 
strobilz which produced only normal ephyre. 
). The greatest variation in the number of arms in the ephyre produced 
from one strobila was from a four-rayed form to a twelve-rayed form. 
Taking the ephyre produced as a whole, the abnormalities which 
occurred varied from a form with three rays up to a form with 
fourteen rays. 
6. The interradial arms appear to be more constant than the perradial 
arms, as instanced by the four-rayed forms, in which it is the 
interradial arms which are present. 
The whole forms a striking example of variation in an asexual 
generation, a field which I hope to work at later, for studying the question 
whether variations produced in an asexual generation are transmitted to 
the succeeding sexually produced generation. a 
