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In G. S. Brady’s Works 1868 a and 1868 b, on the other hånd, some, though only minor,
advances are noticeable. The descriptions and reproductions of the limbs certainly leave much
to be desired, but the author is somewhat more fortunate than his predecessors in interpreting
them. The first and second antennae, the inaudible and the maxilla are explained eorrectly
and the seventh limb is called the „oviferous foot“; the fifth and sixth limbs, of which a
parti-cularly misleading figure is added (1868 b, pl. 41, figs. f, g), are, however, incorrectly explained;
their relative positions bave been inverted and they are called the third and the second maxilla
respectively.
After all these mistakes, due, of course, to the smallness of the object and the curious
type and very concentrated position of the limbs, G. 0. Sars, 1869, pp. 358—359, gives in the
diagnosis of A s ter ope norvegica the first correct explanation of ail the limbs; the description of
these organs is, however, rather incomplete, nor is it i Hustra ted by any figures.
FRITZ Müller’s essay „Bemerkungen über Cypridina“ also denotes an advance
in some respects. The rod-shaped organ is discussed, its capacity as a sensory organ is verified
(cf. p. 164 above); the number and the nature of the gills is established (the occurrence of gills
in forms belonging to this group was mentioned cursorily by this author as early as 1864, p. 73);
contributions are made to our knowledge about the heart and the circulation of the blood
(the occurrence of the heart in these forms was observed cursorily by this author as early as
1864, ju 72; cf. p. 164 above). With regard to the middle limbs, however, F. MÜLLER gives
no information at all „um die Zahl der nur muthmaßlichen Deutungen nicht um noch eine zu
vermehren“.
Our knowledge of this family has subsequently been very considerably increased, especiallv
by C. CLAUS’s work of 1876, G. 0. Sars’s, 1887 and G. W. MÜLLER’s, 1894.
As early as i865 G. O. Sars points out (p. 101) that the species described by \V. Baird
under the name of Cypridina Adamsi seems to form „en distinct Slaegtstyp“, — a distinct
genus type — closely related to the genus Asterope.
In his large monograph of 1894 G. W. Müller states (p. 218) that the then known
forms of the genus Asterope s. 1. may be divided into natural groups; an attempt at such
a division was also made, but the groups that were set up received no special naines. In the
first group there were placed Lobiancoi, G. \V. MÜLLER, 1894, brevis, G. \V. MÜLLER, 1890 and
americana, G. W. Müller, 1890; they were characterized by their short, rounded shells, the
uniting of the fifth and sixth joints of the first antenna and by their short, strong main claws,
always few in number (three or four) on the furca. Agassizi (Fr. Müller, 1870) and fusca,
G. W. MÜLLER, 1890 were to form one group; these two forms were characterized by lists running
in the same direction on the surface of the shell, by the uniting of the sixth, seventh and eighth
joints of the first antenna, by the small number of sensorial filaments on the sensory bristle
of the fifth joint on this limb in the female and by the faet that the furca has onlv three siender
and rather long main claws. Of the other species oblonga (E. Giil PE. 1859), elliptica.
A. Philippi, 1840 and teres (A. M. Norman, 1861) would be closely related to each other; they
were characterized by the faet that the fifth, sixth and seventh joints on the first antenna are
free and by having six main claws on the furca. G. \Y. MÜLLER assumed that norvegica.
The classification of
this family.
The division into
natural groups.
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