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some distance xxp on the dorsal side of the animal; fig. 3f is drawn in such a position as to 

 show the head a little behind the middle of the trunk, and fig. 3 g presents the same animal 

 turned half round, with its genital apertures (r) behind the central point, and the entrances 

 of receptaculum seminis (r') far to the front; so we arrive at the result that the distance 

 from the anterior limit between the trunk and the head along the dorsal surface of the 

 animal to the genital apertures is considerably shorter than the distance from the base of 

 the maxillae past the receptaculum seminis to the genital apertures. (The same proportions 

 also appear in fig. 3 b). — The head is pretty well chitinised; the anterior and lateral parts 

 evenly rounded (fig. 3h); no outstanding frontal and lateral borders. Antennulae (a) rather 

 short, 1-jointed; antennas wanting. The mouth exceeding average size; mandibles robust; 

 hairs of the mouth-border not to be detected (though they probably exist). Maxillulas very 

 small, principal branches short, additional branch wanting. Maxillae middle-sized, normal, 

 with smooth joints. Maxillipeds altogether wanting. The sub-median skeleton forms a plate 

 which fills up the whole surface between the maxillae, but ends a little behind their base. 

 The head quite naked. The trunk naked; trunk-legs and caudal stylets wanting. As in 

 Mysidion, no genital area is found, but each genital aperture possesses (besides the lips), 

 its own skeleton, which consists of a tolerably good-sized, somewhat wry ring (fig. 3e, e; 

 fig. 3i, e) formed of a pretty broad list, but the part of it (fig. 3i, f ') which is turned obliquely 

 inward and forward is more thinly chitinised than the remaining larger part. The genital 

 aperture (g) is placed against that part of the ring which turns towards the median line of 

 the animal, and the muscles (m) by which the aperture opens go in the opposite direction; 

 to the front, in the list of the ring itself, is a good-sized hole (k), which is the orifice of a 

 gland. The distance between the two rings varies from being a little larger (fig. 3g) to 

 much smaller than the diameter of each ring. Far in front of the genital apertures are 

 seen two knots at a short distance from each other (fig. 3b, r'; fig. 3g, r', and especially 

 fig. 3e, o), which show, as it were, irregular cracks in the thick chitine; most likely we 

 stand here at the entrances of the receptaculum seminis, though I have not been able to 

 trace regular holes, nor have I found spermatophores on the females. The receptaculum 

 seminis (fig. 3e, r) is large, odd and much broader than long; at each end it curves evenly 

 backward, and continues as a wide, centrally somewhat narrower, and distally again ex- 

 panding duct, which is about parallel with the other duct and runs up to the genital 

 aperture itself. 



MALE. The body is not a third longer than broad, of a tolerably normal shape, 

 but altogether hairless (fig. 3 k and fig. 31). The head somewhat longer than the trunk, but 

 the latter somewhat broader; the frontal border strongly produced, and the lateral borders 

 well developed; on a line with the front extremity of the maxillae, and on the border between 

 the sides and the back, we see the two low conical eminences. Antennulae extremely short, 

 1-jointed, with a single seta (b) which is olfactory and several times the length of the antennula. 



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