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the peduncle, which is evidently almost limited to the zone where 
new scales and plates arise, i. e. the transition from capitulum to 
peduncle, the peduncular scales thus will form oblique series ascend- 
ing from the ventral (rostral) to the dorsal (carinal) side of the 
peduncle. 
Little by little the lower series of latera now arise, always one 
new plate below the intervals in the precedent row. Much livelier 
a b 
Fig. 15. Mitella polymerus f. typicci; La Jolla. a specimen with peduncle scales only 
rostrally and laterally; b somewhat older specimen showing the oblique series of de- 
veloping peduncle scales; c rostral, d lateral, e carinal aspect of the capitulum of an 
adult specimen. [a—b x 22, c—e natural size], 
nevertheless is the formation of peduncular scales, and though the 
growth of the capitulum now becomes ever more slow, and the form¬ 
ation of new capitulum plates soon finishes, the growth of the stalk, 
and the development of new peduncle scales just below the capi¬ 
tulum seems to be continued through all the life of the individual, 
and always according to the same rule. Thus the oblique serial 
arrangement of the scales is kept, although it sometimes is a little 
obscured in larger specimens, owing to accidental contractions. 
Thus here as in Scalpellum we may put down as a fixed rule, 
that new (accessory) plates are always developed at the transition 
from capitulum to peduncle. The scales of the peduncle almost 
entirely abuse their growth, when they have been removed some 
way from their zone of origin. I have never been able to confirm 
