CHAPTER X. 
Sub-Order Lortcava,. 
Integument stiffened to a wholly, or partially, inclosing shell ; foot various. 
Family XI. RATTULIDA, 
[Body cylindric or fusiform, smooth, without plice or angles ; contained in a lorica 
closed all round, but open at each end, often ridged; trophi long, asymmetric ; eye 
single, cervical. Generally subject to abnormal conditions. 
This family comes first in the Loricate sub-order, because the loricate structure is in 
varied condition; for, whereas in some species it is indubitable, in others, which yet can- 
not be severed from these, the integument is still thin, flexible, and membranous. 
Ehrenberg, indeed, while he assigned M. carinata to the Loricata, removed his genus 
Monocerca far away to Il-loricata. Yet that carinata and rattus are congeneric cannot 
be doubted by anyone who knows both; bicornis certainly goes with the latter, The 
sausage-shaped species have many family affinities with these ; though subdivisible inter 
se. The peculiar form of trophi represented in figs. 60-62 of my Memoir ‘‘ On the Manduce. 
Organs”’ runs with little variation through all. 
The most curious peculiarity in the family is its tendency to asymmetry, which 
appears in many organs. In the mastax the right malleus always differs from the left; 
when there is an elevated ridge on the dorsum, it is apt to be bent over on one side, and, 
instead of running straight down the middle, to pass slantwise from right to left; when 
two antenne are present they are unequal. The toes, sometimes normal, are often 
reduced to a single style, with minute sub-styles grouped around its base. In other 
cases they are modified in a most unprecedented manner, described under the genus 
Calopus. On the whole, it is a group of very peculiar interest, both to the scient and to 
the intelligent seeker for amusement.—P.H.G.] 
Genus MASTIGOCERCA, Ehrenberg. 
(GEN. CH. Body fusiform or irregularly thick, not lunate ; toe a single style, with 
accessory stylets at its base ; lorica often furnished with a thin dorsal ridge. 
The terminal style is by no means a tail, but a true toe, however modified. The 
homology of the sub-styles is not clear. The surface of the body is usually smooth and 
polished, often elegantly tapered; nor does the thin elevated carima of the dorsum 
materially interfere with this elegance, which the long taper toe admirably finishes. 
This organ, though inflexible throughout, is capable of rapid and sudden motions, being 
bent right and left, and whisked to and fro with great agility. The mastax is usually 
pear-shaped and very long, but the esophagus, a sinuate duct, leads from it almost at 
its very summit occipitally, just where the mallei work upon the incus. Thus the great 
length of the mastax does not intrench on the needful length of the stomach, since this 
viscus begins far forward. The muscles, in many species, especially the transverse series, 
have been well resolved. Muciparous glands are richly supplied. Surprise is often felt 
that Rotifera with but a single style should be able to maintain so firm a hold upon 
