222 BUNTING. [VoL. IX. 
segmentation in the Oceania armata Koll, in which he traces 
it to the planula (PI. I, Figs. 34, 35). 
That in some instances these irregularities in segmentation 
might affect the planular stage, was suggested by the fact 
that very many peculiar forms of planulae were found inter- 
mingled with the normal ones. The most noticeable among 
these was one having an anterior blunt end and two posterior 
pointed ends giving it a A shaped appearance (Fig. 36); others 
consisted each of two processes united simply at their anterior 
ends, their two processes extending directly out from one 
another like two wings ; again the anterior end of one planula 
would be attached to what appears to be the posterior end of 
another one; others would appear with a constriction in the 
center, giving the planula a somewhat dumb-bell shape ; often 
these latter ones would be observed in pairs lying directly 
across one another. In all these forms each portion was about 
half the normal size, strongly pointing toward the fact that 
they were derived from the same ovum. Those planulae having 
a blunt anterior end, with two pointed posterior ones, attached 
themselves to the dish at the broad end. I watched them in 
order to find out, if possible, whether divisions into individuals 
appeared thus early in Hydractinia, or whether twin hydroids 
would be developed. Although carefully observed for a week, 
and placed under favorable conditions, the development pro- 
ceeded no further ; but this is not to be regarded as indicating 
that development was impossible, since an enormous percentage 
of the normal planulae did not develop beyond the attached 
planular stage. 
ADULT ABNORMALITIES. 
The reproductive polyp with adult gonophores was found in 
one instance as a bud coming off from the nutritive hydroid. 
Hincks has figured a bifurcating zooid of Hydractinia, in which 
there is a nourishing polyp and a reproductive one, although 
the latter has no gonophores ; while Agassiz has shown a 
bifurcation of the spiral zooids. 
In a few cases fission of the nutritive hydroid was also seen; 
thus besides the usual sexual method of development, we find 
