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Maxillae with a long, sinuous edge and a great number of nearly equal spines. Those 

 at the upper corner are slightly larger and another group of the larger spines is planted at 

 one-fourth the height from the inferior angle. The apodeme is stout and not very long. 



Outer maxillae are well-developed with the bristles of the nearly straight inner 

 margin divided into two separate tufts, separated from one another by a little excavation without 

 bristles. Exteriorly they are swollen and not very densely beset with bristles. The opening 

 leading into the body-cavity is large and situated on the top of a rounded protuberance. 



Cirri. First pair short and very stout; rami not very unequal in length; much more 

 so in the number of segments, and especially in breadth (PI. \T, fig. 6). The anterior segment 

 has nine, the posterior sixteen segments. The segments of the anterior ramus are oblong in 

 transverse direction and are only united with one another over part of the breadth ; the segments 

 of the posterior ramus are as broad as they are long, with the exception of the first segment 

 which is longitudinally oblong. In both rami the segments bear numerous spines along their 

 margins, the outer segments over the whole surface. 



Second-sixth cirrus differ from one another mainly in length; this difference is 

 greatest between the second and third cirrus. In the second cirrus the anterior ramus is moreover 

 a little broader than the posterior ramus, in the other cirri this difference does not exist. All 

 the cirri give one the impression of being stout and well-developed. 



Caudal appendages small, composed of six cylindrical segments, the width of which 

 diminishes considerably from the first to the last; each segment bears a few very delicate bristles 

 at the extremity; the last segment has about half a dozen longer ones on the rounded apex. 



S e x. The specimen investigated showed no trace of male genital organs : neither 

 testicula nor penis ; I think this species must be considered as belonging to the group of 

 unisexual species of which I discovered several representatives when studying the Cirripedia of 

 the "Challenger" expedition. The specimens the description of which is given above were 

 probably all females. 



Males. At first I could not find the males of this species. At last I found them on the 

 large specimen of Station 5 : very small bead-like individuals attached in great number to the 

 surface of that part of the sack or mantle of the female which connects the inferior halves of 

 the two scuta at their occludent margin. I counted well over a hunderd of these little animals. 

 Each of them is enclosed in a chitinous sack and are placed so near one another as to touch 

 and even to flatten each other mutually. Fig. 9, PI. Vl represents a group of three of them ; 

 in fig. 8 one of them is seen a little more enlarged. They are attached to the outer surface 

 of the chitinous sack of the female with their small antennae, and their surface is hirsute with 

 very short spines. The ojaening giving entrance to the interior of the sac is at the top of a 

 little conical papilla which projects beyond the surface of the remaining part of the sac. Round 

 the opening are four very small calcareous parts like so many rudimentary valves and between 

 these, small excrescences with short hairs, like minute tentacles, are planted. I have not been 

 able to study the internal structure (which can be done by making microtome sections only) 



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