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The exopodite of the first pair of feet is composed of two joints. The second and third 
joints are completely fused together. The junction of the two joints is defined by an outer-edge 
spine. The endopodite is one-jointed. 
The exopodite of the second pair of feet is three-jointed. The endopodite is two-jointed. 
The second joint of the endopodite is furnished with three transverse rows of spines. 
The exopodites.and endopodites of the third and fourth pairs of feet are three-jointed. 
The second and third joints of the endopodite of the third pair of feet are each furnished 
with two transverse rows of spines. The second joint of the endopodite of the fourth pair of 
feet is furnished with one transverse row, and the third joint with two transverse rows of spines. 
The surface of the joints is closely set with minute points. 
The fifth pair of feet is very small and rudimentary. Each foot consists of two free 
joints attached to a basal part. The second joint is moderately stout and spiniform (Plate 
DOOM, fig. 9). 
Occurrence. — One specimen was obtained from the plankton collected with the 
HENSEN vertical net at Station 143, 1000 metres to the surface. | 
This species appears to be identical with the form described by Sars (1907 a). The only 
difference that can be made out between the preliminary description, and that now given, is 
in the jointing of the endopodite of the third pair of feet. Sars states that it is two-jointed, 
whereas in the ‘Siboga’ specimen it is distinctly three-jointed. It also appears to be identical 
with Amallophora dubia, described by my father from males only, that were found in plankton 
collected in the Gulf of Guinea. The two large amadlla on the apex of the first pair of maxilli- 
pedes, are clearly shewn amongst the other illustrations (Plate IV, fig. 13) in the report, ‘On 
Entomostraca’ from the Gulf of Guinea. 
I have included Amallophora and Heteramalla in the family Phaennidae, as the sensory 
appendages on the apex of the first maxillipedes are quite distinct from those found in the 
family Scolecithricidae. The ciliated heads indicate a closer relationship to Phaennua than to 
Scolectthrix. 
8. Family SCOLECITHRICIDAE, 
Genus Scolecithrix Brady, 1883. 
Brapy established this genus for the reception of a Calanoid form described by Lusgocx 
as Undina danae, which is distinguished by the presence of a tuft of worm-like sensory filaments 
on the apex of the first pair of maxillipedes. The fifth pair of feet is entirely absent in the female. 
A second form, Scolectthrix minor, with a fifth pair of feet in the female, was also 
included under the genus by Brapy. Gressprecur and Scamett subsequently included a number 
of species under the genus, the females of which are furnished with fifth feet. Sars rightly 
points out, however, in ‘Crustacea of Norway’, that the inclusion of Scodecethrix-like forms with 
a fifth pair of feet is erroneous, and established a new genus for the reception of some of them. 
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