NOTES ON A PECULIAR FORM OF POLYZOA. 7 
the base of the zocecium passes obliquely backwards and 
upwards, expanding in a fan-shaped manner, to be inserted 
into its hinder wall to the height of about one third or one 
fourth of the zocecium (fig. 1a). The action of this muscle 
must be to draw the entire zocecium downwards and for- 
wards, or, in other words, to bend it on itself, and thus, by 
the conctitrent action in many zocecia, to curl the branches 
forwards ; an action that has, in fact, been noticed by Koren 
aiid Danielssen in the living condition. Besides this flexor 
muscle in A. cyathus there is an additional, smaller, fan- 
shaped bundle of fibres, for the purpose, apparently, of 
curving the step-like process of the wall of the zowecium, upon 
which the avicularium is fixed, forwards, so as to causé the 
avicularium to come in front of the zowcium (fig. 1c), which 
appeais in the spirit specimen to be its usual position. I 
have been unable to discern aiiything like ovary or testis 
within the zocecia; but many, if not most, of the ovcia 
are filled with an apparently vitelline mass or ovum of large 
size. 
Koren and Danielssen are inclined to consider that their 
Kinetoskias Smitit is identical with Naresia cyathus of 
Wyville Thomson; but, so far as Iam able to judge, from 
their detailed description and figures, I do not see how this 
can well be. The form and size of the zocecia and of the 
avicularium and ovcia undoubtedly appear to correspond 
with those of B. cyathus; but the general aspect of the 
zoaritim it the two cases is utterly dissimilar. In this par- 
ticular, however, it must be remarked that the natural-size 
figure given if pl. iii! does not at all correspond with the 
description in the text. 2. In A. cyathus there are no traiis- 
verse ruge@ on the back of the zoweva. 3. The avicularium 
is attached in B. Smti above the middle of the otiter 
border of the zocecitm, whilst in A. cyathus it arises from a 
distinct step-like process, quite at the bottom. 
On these grounds there does not appear to me sufiicieiit 
reason to regard Kinetoshias Smittu and Naresia cyathus as 
specifically the same. 
2. Kinetoskias pocillum.Though very tiuch smaller than 
K. cyathus, the structure of the zoatiuin is exactly the sariie. 
Like that species it consists of a vasifoii iifundibuliform 
expansion composed of branches springing from a common 
point, and, as in that form, united at their base by a trans- 
parent membrane, which is coiiiiected with an equally trans- 
parent, terete, iémbranous stem; about ore and a half to 
two inches high, which, as in A. cyathis, tevminates inferiorly 
OH, ¢: 
