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Juday, Chancey (ed.) / Transactions of the Wisconsin Academy of Sciences, Arts and Letters
volume XXI (1924)

Pearse, A. S.
Observations on parasitic worms from Wisconsin fishes,   pp. [147]-160 PDF (4.1 MB)


Page 149


Pearse-Parasitic Worms From     Wisconsin Fishes.
  Host: the short-nosed gar, Lepisosteus platostomus Rafinesque.
  Description: Body slender; length 2.4 mm.; width, .25 mm.;
covered with sharp spines, which decrease in size posteriorly. In
the region of the pharynx there are about fifty spines on the cir-
cumference of a cross section of the body. The diameter of the
acetabulum is slightly greater than that of the oral sucker, which
measures .08 mm. The acetabulum is at the posterior end of the
anterior seventh of the body.
  A slender prepharynx is present. The pharynx measures
.012 mm. in length and .088 in diameter. The slender esophagus is
about twice as long as the pharynx. The intestinal rami are slen-
der, join the esophagus more than the length of the esophagus
anterior to the acetabulum, and extend nearly to the posterior
end of the body.
  The genital pore lies on the median line, just anterior to the
acetabulum. The testes are ellipsoidal, their longest axis being in
the same direction as that of the body. They are about equal
in size, measuring .18 mm. in length. The anterior one is situated
on the left side at the beginning of the posterior third of the body.
The posterior one is slightly toward the right side, just in front
of the posterior sixth of the body. The cirrus sac is long, thick,
and somewhat sinuous, extending from some distance posterior to
the acetabulum to the genital pore.
  The ovary is ellipsoidal and about half as long as a testis. It is
situate-nearheodl          thedmideowar                 the left
side. The vitelline glands are small, irregular in form but gen-
erally spherical; and distributed along each side of the body from
a little posterior to the acetabulum to the posterior testis. The
uterus is coiled from the genital pore to the posterior end of
the body. It usually contains a couple of hundred eggs which are
elliptical, without a distinct cap, and measure .04 mm. in length.
  Eleven specimens, including the type, were taken from the in-
testine of a short-nosed gar on July 11, 1920. Four other speci-
mens were found in bullheads caught in the slews at the outlet of
Lake Pepin: three in an Ameiurus natalis on July 6, 1920; one in
an Ameiurus nebulosus, July 7, 1920.
                Crepidostomum illinoiense Faust
                            (Fig. 7)
  Specimens studied: Cat. No. 7626, U. S. National Museum; June
25, 1920; Lake Pepin, Wisconsin; Collector, A. S. Pearse.
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