328 
The Ohio Xaturalist. 
[Vol. V, No 6, 
total width of the peristome was aljout two-thirds of the adult 
form. In two minutes more it had assumed the form shown in 
Fig. 3, the posterior end had narrowed considerably and while 
the constriction extending from the posterior ciliary wreath was 
still one-third the total length of the body its attached end had 
assumed the appearance of the adult pedicle. The lengthening 
of this pedicle had every appearance of growth and not of meta- 
morphosis of body into pedicle. The body while producing the 
pedicle was actually larger than before, and although the form 
was feeding rapidly it is hardly conceivable that assimilation and 
growth could take place at the rate at which the pedicle aj)peared. 
/ j, J y 
DESCRIPTION OF PLATE. 
Fig. 1. Four stages in the growth of the pedicle of Ephistylis flavicaus 
Ehr. p. c. — posterior circlet of cilia, p. — pedicle appearing first 
in Fig. 3. 
At the end of five minutes more (Fig. 4) the body of the 
animalcule was nearly normal in every respect except that the 
slight elevation on which the posterior circlet of cilia had been 
situated could still be observed although the cilia had been 
retracted. The pedicle at this time was one-sixth the length of 
the body and the animalcule was feeding actively. From this 
point on only the relative rate of growth in the pedicle will be 
given as no opportunity offered to note any other histological 
changes than those pertaining to the lenghtening of the pedicle. 
At the end of five minutes more or a total of fifteen minutes 
in all the pedicle was equal to one-fourth the length of the body ; 
in twenty minutes one-third ; at twenty-five minutes one-half ; 
at thirty minutes, thirteen-twentieths; at thirty-five minutes, 
four-fifths, and at the end of forty minutes equaled the body in 
length. 
It was not observed again for a ]>eriod of forty-five minutes 
during which time the pedicle had attained a length equal to 
three times that of the body. This is somewhat under the nor- 
mal, the unbranched pedicle usually being four to five times that 
of the body. So that a period of one hour and a half was suf- 
ficient to produce a pedicle nearly equal to the unbranched por- 
