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developed additional branch. The basal joint of the maxillae with a conical process on the 

 boundary between the inner side and the posterior side. The maxillipeds tolerably robust; 

 the basal joint smooth and naked; (whether the second and the third joints are separated 

 could not be made out with certainty); the last joint has a few short setae inside its point. 

 The sub-median skeleton has narrow lists inside the maxillae and a well-developed list between 

 the head and the trunk behind the base of the maxillipeds; no hairs on the skeleton between 

 the appendages. The lateral margins of the head naked. The trunk naked; the trunk-legs 

 distinct. The genital area (fig. 4a) much narrower than the head, much broader than long; 

 the solid chitinised part forms a somewhat sinuous semi-circle, which posteriorly has a narrow 

 interruption at the median line, and anteriorly a very broad opening; the hindmost sub- 

 median part is nearly straight, the anterior corners bent inward; the ring itself is rather 

 narrow except outside the posterior extremity of each genital aperture, where it expands on 

 the inward side. The genital apertures are large, strongly curved and situated close together; 

 the well-developed caudal stylets are found in very close proximity on the soft skin which 

 divides the ring on its posterior side. The genital area is naked, except a number of very 

 fine hairs on the ring near the caudal stylets and on a smaller spot behind them. 



MALE. The only specimen (fig. If — lg) is '20mm. in length; its breadth is a little 

 more than two thirds of the length. This shows that it is tolerably small compared with 

 the chief bulk of males, but extremely large compared with the female (fig. 1 b : fig. 1 a). The 

 animal is flatly rounded anteriorly and with very obtuse angles in the middle of its lateral 

 margins; its head is only a trifle larger than its trunk. The front is feebly produced, its 

 margin is naked. Antennulae, antennae, mouth, maxillulae and maxillae much as in the female. 

 Maxillipeds of medium length, the basal joint with smooth inner margin, and a moderately 

 large part of the outer surface provided with hairs, these, as usual, arranged in stripes and 

 spots; the terminal joint as in the female. The sub-median skeleton with all three pairs of 

 processes developed; the first pair, behind the maxillae, are broadly rounded, depressed, 

 plate-like; the second pair long, slender, almost cylindrical and strongly diverging; the third 

 pair are situated at some distance from each other between the second pair and are not 

 half the length of these. The lateral margin of the head is furnished with hairs (and as in 

 much the greater number of species, this hair-covering begins in front of the base of the 

 antennulae), continues in an oblique direction upward and backward across the side and 

 the back, forming laterally a rather narrow band of moderately long hairs, being reduced 

 on the back almost to a line of very long hairs. Behind this line the back has a long, 

 naked transverse area, whereas the remainder of the back, the sides, the posterior extremity 

 and the ventral surface — except on its foremost part — are closely covered with hairs of 

 medium length. The dorsal and upper lateral parts of the head have hollow spaces beneath the 

 skin. The first pair of trunk-legs are short, with a broad basal part and two short, sub- 

 cylindrical branches situated far apart from each other; the outer branch ending in two 

 setae, one of which is about the length of the second joint of the maxillipeds, whereas the 



