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Skinner, Ernest B. (ed.) / Transactions of the Wisconsin Academy of Sciences, Arts and Letters
volume XV, Part I (1904)

Marshall, Wm. S.
The reproductive organs of the female maia moth, Hemileuca maia (Drury),   pp. [1]-Plate II ff. PDF (3.9 MB)

Page 3

Marshal-1Reroductive Orqans of the Female Moth.      3
       tubules, these are not bound together in any way, but each one
       throughout its entire length is separated from the others. Be-
       fore the expulsion of the eggs each tubule is from 70mm. to
       80mm. in length. The number of eggs each contains is not
       constant, thirty-eight being the average in those counted. The
       four tubules on each side unite to form an oviduct, 1.5 mm. in
       length, and the two oviducts join in the median line to form an
       oviductus communis 2 mm. long.
         Throughout the entire length, from the distal end of the
       tubule to that point where the oviductus communis passes into
       the vagina, the wall is very similar in structure. On the inner
       surface there is a folded chitinous layer, somewhat thinner near
       the distal end. The next layer, the epithelial, has, as such,
       nearly disappeared, and in its place is an empty space contain-
       ing a few scattered nuclei each of which shows a few irregular
       chromatin granules. The cytoplasmn, which we can assume was
       present when the cells were active, has entirely disappeared.
       Externally each tubule is lined with two muscular layers, an
       inner circular, and an outer longitudinal layer. Throughout
       the entire length of the tubule there is only a very slight, if
K     any, difference in the comparative thickness of these two layers
       (Figs. 5 and 6). Sections cut through the distal end and the
       middle of the tubule will show this.
         The oviductus communis shows a slight change from what we
       have just described for the ovarian tubule. The remains of the
       epithelial cells are much more marked, the nuclei appearing at
       fairly regular intervals, and the cell boundaries, while not com-
       plete, are present in such a condition as would allow us to limit
       the boundaries of the cells which were earlier present in this
       layer. Both muscular layers show a greater development (Fig.
       7), and while the circular longitudinal layers bear to each other
       the same relative thickness that they did in the tubule, both are
       here very much thicker. In all specimens of iemileuca exam-
       ined the eggs were fully developed, and in most of the moths
       they had been in part or entirely expelled from the body. The
       egg-laying goes on rapidly, and but a short time is needed for
       the expulsion of all the eggs from the body. The only use the

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