THE FLEXIBLE CREEPERS. 
477 
the order Notommatina* One mark of a typical group, 
almost constant, is that it contains a larger number of sub- 
divisions than any other group of like rank ; and populousness 
is highly characteristic of the Notommatina. 
All these animals are permanently free, never becoming 
fixed to other objects, and never forming mutually adherent 
groups. Their bodies are not inclosed in a tube ; and their 
skin is for the most part flexible, not forming a shelly mail, 
though in one or two genera certain portions of the integu- 
ment are stiffened, indicating an approach to the structure of 
the mailed families. The form is generally cylindrical, with 
a length about twice the diameter on the average, occasionally, 
however, three or four times the diameter. The front does not 
expand into a flower-like disk, but is usually no wider than 
the body, very varying in its shape, sometimes being flattish, 
oftener convex, with many swellings, beset with strong 
vibrating cilia, which are so arranged as that their combined 
action produces two vortices, one on each side of the head. 
The opposite extremity of the body terminates in a thick foot 
of several joints, of which the last bears two diverging toes. 
These are used by the animal for its support, to aid it 
in crawling. They are in general moderately short, but in a 
few cases are of great length. 
The characteristic appearance of the little animals of this 
order will be seen by reference to Plate XIX., in which figure a 
represents a dorsal view of Eosphora anrita, in the act of 
, swimming. This is an elegant and sprightly species ; espe- 
cially beautiful when, as is very frequently the case, the 
enormous stomach and intestinal canal are filled with trans- 
lucent green food. I have repeatedly met with it around 
London; as in a green pond in Greenwich Park, and in the 
tiny sweltering pools on Hampstead Heath, renowned, for 
more than a century, as being prolific nurseries of the higher 
forms of Rotifera. They will live and increase their race in 
a phial of water containing a little growing vegetation, as a 
sprig of water-moss, a few leaves of duckweed, or a small 
tangle of converva : the phial being left uncorked, and set in 
the light, but protected from the direct rays of the sun. Here 
they will play and rout about, delving in the sediment that 
* This order is nearly concurrent with the family Hydatincea of Ehrenberg. 
But the genus Hydatina, which he considered typical, and whose name he 
used for the family appellation, consists of only a single species, and cannot 
be separated from the great genus Notommata, except by the very trivial and 
valueless character of wanting an eye ; or rather, of wanting the speck of 
coloured pigment which ordinarily accompanies the eye. H. scnta is a 
true Notommata. 
