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Page:Popular Science Monthly Volume 7.djvu/669

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BATS AND THEIR YOUNG.
649

Embryo Bats. All, excepting Fig. 11, enlarged 5 diameters.

Explanation of Plate[1]

Figs. 10 and 11 from the little brown bat (Vespertilio subulatus), the others from a Brazilian species (Nyctinomus Brasiliensis); Fig. 11 and the smaller part of Fig. 5 are of natural size. All the others are enlarged 5 diameters; that is, 25 areas. The lettering is uniform, as follows: u c, umbilical cord; not seen in 5 or 8. H, head; T, tail ; Ar, armus or anterior limb; Pes, foot; P, pollex or thumb, the anterior digit of the manus; Pr, primus or great-toe, the anterior dactyl of the pes, which becomes the outer in the older bats, but is the inner with most animals; W, web, the fold of skin which connects the digits with each other and with the leg and margin of the trunk; C, calcar, a spur-like process from the heel, serving to extend the web which reaches between the legs and the tail; Ear, the ear; in Fig. 7 H is the heart; in Fig. 10 A is the rounded prominence corresponding to the cerebral hemispheres which are developed from the anterior cerebral vesicle; M represents the optic lobes, formed from the middle vesicle; N, nostril; Mo, mouth; E, elbow; K, knee. For further explanation, see the text.
  1. Figs. 5 to 11 were all drawn and engraved from nature by Mr. Philip Barnard.