NOTES ON SOME FREE-SWIMMING ROTIFERS. 147 
at the base. I am now convinced, however, that it belongs to 
another Genus of the same Family, viz., Diglena, and it seems 
most to resemble D. forcipata. Characters: cylindrical, slender 
(my? specimens were rather stout), obliquely truncated anteriorly ; 
toes recurved and longer than stout foot; eyes two, black ; cilia, 
very fine, covering the oblique anterior region ; the carapace seems 
too large for it ; it is continually altering its shape, and in its general 
movements it much resembles Lindia, hence an old name for it 
was L. vermicularis. The Family Hydatinzea, is described as con- 
sisting only of illoricated Rotifers ; however, the integument, in this 
particular instance, is so thick and strong as to justify the use of 
the term carapace. This is shown in Fig. 234, which is the anterior 
portion of carapace or lorica, showing two spines and covered 
with minute tubercules. It is a very transparent Rotifer, and its 
beautiful and characteristic gizzard is shown (enlarged) in Fig. 234 
This differs, slightly, from Pritchard’s figure, but it correctly repre- 
sents the one I saw. Fig. 24. This Rotifer is one entirely new to 
me, and is of great interest, because it seems partially to fill up a 
gap previously existing. We have Triarthra and Polyarthra, and 
this one is a Monarthra, or one-spined Rotifer. It is, however, a 
very peculiar form, and will require more careful study than I have 
been able to bestow upon it. I have, as yet, only seen three 
specimens, and always grubbing about among decaying vegetable 
matter, which fact, coupled with their minuteness, renders their 
study one of some difficulty. Characters: obliquely truncated in 
front; anteriorly cylindrical for about 3 its length; enlarging 
from thence to about the middle, when it gradually tapers, on the 
ventral side, to the toes, on the dorsal, to base of foot, where it is 
suddenly attenuated ; foot short ; toes three, about length of foot, 
one situated dorsally and slightly behind the other two ; eyes none; 
having a frontal hood like Stephanops; cilia in bundles; a long 
tapering spine proceeds from centre of dorsal region; internal 
organs difficult to make out, for reasons previously stated. It has, 
however, a gizzard, the details of which I hope to make out when 
I come across another specimen. The frontal hood, for a long 
time, I considered merely as hooks, but on further acquaintance I 
am convinced that what I saw was the optical expression of a hood. 
I may, however, be mistaken in this, but think not. I procured 
them from a long ditch containing Anacharis, and a large quantity 
of Nitella, &c. I intended sending sketches and descriptions of 
two or three other less-frequently recurring forms, but must defer 
doing so to a subsequent issue of the Journal. These descriptions 
are very imperfect and most certainly are not strictly in accordance 
with my own opening remarks ; I am not, however, “an authority,” 
but only an enthusiastic student of nature, desirous of knowing 
more about the charming animals which I have made the subject 
