University of Wisconsin Digital Collections
Link to University of Wisconsin Digital Collections
Link to University of Wisconsin Digital Collections
The State of Wisconsin Collection

Page View

Transactions of the Wisconsin Academy of Sciences, Arts and Letters
volume XXIII (1927)

Harring, H. K.; Myers, F. J.
The rotifer fauna of Wisconsin. IV. The Dicranophorinae,   pp. [667]-Plate 49 ff. PDF (41.5 MB)


Page 668


668 Wisconsin Academy of Sciences, Arts, and Letters.       I
be considered a monograph of all existing Dicranophorinae;
very evidently it deals with only a small fraction of the
species that will eventually be described. Nevertheless,
fragmentary as the work admittedly is, it may be of some
service in making comparisons with the fauna of other
reoP1ns  vithout timP-PonnQmrinof                 -4 Al 1
HWJ
the'
has
tudii
fled
of ti
sxe1--K V~lbl.---/ lil-JW-Wl~o~l~l~l~s~j --- II ...V ucll  " eLIIU
also
 4  open
as the only substitute for identified type material at present  fuler
available.                                                           closi
  We are indebted to Mr. David Bryce and to Mr. F. E.           In
Cocks for essential material from England, and to Dr. P.      the:
de Beauchamp for drawings and   material collected in     I   semi
France, and also for his friendly advice and coopera-          roug
tion. Herr J. 1-auer, of Uoereschach, Baden, kindly sent
us material of what proved to be an undescribed species,
which we take pleasure in naming for him.
  In subdividing this group consideration has been given
not only to the inert contour of the trophi, the sclerified
parts of the mastax wall, but also to the musculation, which
is probably less subject to specific variation and of deeper
significance. The most primitive rotifer family, the Notom-
matidae, must have divided early into two branches, the
Notommatinae, plant and detritus feeders, and the Di-
cranophorinae, carnivores. The originally malleate mas-
tax has been correspondingly modified, the terminal types
being the virgate or pumping and the forcipate, each with
its subtnes. 'y ' T most mr mf 4rimit ix+-r f   of +Ih for,+te
their
mid-
man,
tens(
  T1
Dier
by I
able
Stre]
opho
nece
  E]
trurr
basa
               -_-Z,_.1   -ittl--: t~tl---'blVU ..YJ1J VJ --1C --1Wl->;
 they
mastax is found in Dicranophorus, as constituted here; the    The
mallei have been turned into the plane of the incus and the   extei
entire mastax is longitudinal with reference to the axis of     A
the body. The unci have retained but a single tooth,          aituri
showing occasionally remnants of a second; but they are       cies,
hinged at or near their tips on the rami, the whole forming   de E
a highly efficient grasping organ. The muscles belonging      conv
to the mallei are well developed, the flexors attached to     mati
the external edges of the rami and the posterior ends of      pate
the manubria, the extensors to the anterior edges of the      tensi
unci and the external edges of the manubria, passing over     the i
the joint.                                                           hydr
  In Encentrurn the malleus muscles have been lost and the    view
weak, needle-like unci ankylosed to the external edges of     the i


Go up to Top of Page