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has no bristles at all. One of the bristles on the next distal joint and two of those on the end joint,
among them the one situated most distally, are comparatively long and stiiï. of a more or less
ordinary type, annulated proximally, more or less hyaline distally, ail presumably playing
a certain part in seizing and holding the female fast. The most distal of these bristles is, in most
species of this genus, armed on the posterior side at about or somewhat distally of half its length
with a smaller or greater number of spines, which in most cases point proximally; in a number
of cases the armature of this bristle is of other types. The other two of these three bristles
are usually somewhat shorter than the most distal one and are either quite bare or only slightlv
armed. On the proximal one of them there is rather often a more or less long pad-like appendage
(„Schwiele“, according to G. W. Mt’l.LER’s terminology) at about the place corresponding to
the distal bristle’s rows of spines. G. W. MÜLLER describes this appendage (1906 a, p. 39) as
„eine zartwandige einseitige Verdickung der Borste“. This author then writes: „Wie das Bild
zu stände kommt, ob es sich wirklich um eine Erweiterung der Borste oder nur um einen häutigen
Anhang (resp. zwei) handelt, weiß ich nicht.“ According to what I established with certaintv
in a number of species, we are not concerned with a lamelliform, but with what I may perhaps
call a pad-like appendage (cf. G. H. Fowler, 1909, p. 230) that is situated along one side bf the
bristle. In all the species investigated by me this pad had transverse folds (somewhat like the
bellows of a camera); cf. my fig. 3 of C. bispinosa and fig. 7 of C. borealis. G. \V. MÜLLER
states that two such appendages are sometimes found on the same bristle, one situated opposite
the other. This statement is presumably always due to a mistake; in a number of cases, e. g.
in C. antipoda, G. W. MÜLLER, 1906 a, pl. XXVI, fig. 9, I have verified the fact that it is a mistake.
An apparently double-sided pad of this sort, as shown in the figure just mentioned, originates
from the fact that a comparatively high pad, placed on one side, becomes visible on both sides
of the bristle under the pressure of the coverglass. One of the next distal joint’s bristles and one
of the end joint’s proximal bristles are developed as thin-walled, bare sensorial filaments, in most
cases somewhat rounded distally (as in, for instance, fig. 7 of C. symmetrica); they are developed
in somewhat different ways in different species.
F e m ale: — This is of about the same type as that of the male, but is rather
consider-ably shorter and weaker. It lias rather weakly developed musculature and often a rather
indistinct division into joints; the number of joints is sometimes the same as in the male,
sometimes it is more or less reduced by complete junction of two or more joints. The proportions
between the (original) joints are about the same as in the male. (If nothing special is mentioned
in the following descriptions of species, the proportions between the joints are about the same
as are shown in the adjoining figure 10 of C. symmetrica.) The number of the bristles is either
the same as in the male or else the dorsal bristle of the second joint is absent. The latter bristle
is, if developed at all, pointed, of the ordinary type and does not grasp the rod-shaped organ.
(The latter is consequently iree from this antenna.) Of the five bristles on the two (original)
distal joints the distal one on the end joint is, as is the case in the male, long and of the ordinary
type, annulated proximally and more or less hyaline distally; along its posterior side at or in
most cases somewhat distally of the middle it has a greater or less number of short hairs; in
some cases it has, in addition, along the proximal part of the anterior side a number of more
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