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as a rule more to the left and at the bottom of the sack. When two were present (PI. IV, 

 fig. 20) they were so placed' that the anterior portion of the one touched the posterior end of 

 the other. I never observed that a much constricted part of the males passed through the skin 

 (sack or mantle) of the female; there is as a rule a thickening of cement round about the base 

 of the peduncle. The e.Ktremity of the peduncle with its cement-ducts passes through this cushion 

 of cement, but I never observed that it also went through the wall of the sack (or mantle). 



The figures 3 — 8 of PI. V are drawn from a male of 3,5 mm. Darwin calls the part in 

 front of the oblique fold the thora.\, the rest the peduncle of the animal. The thorax supports 

 two pairs of rudimentary cirri and, more to the so-called ventral side, the parts of the mouth. 

 The labrum is very broad with a nearly straight edge and small palpi. The latter have a few 

 short bristles or hairs at their pointed extremity. The mandibles have three teeth, more diverging 

 than in the females; the inferior edge is quite undeveloped: a mere nob with a rudimentary 

 point or spine at the extremity. The maxillae show the three upper spines and two more spines 

 at the inferior end of the edge separated by a notch from the upper spines. The two stand 

 at a little distance from one another and are considerably shorter than the upper spines, two of 

 which are ag^ain .stronger than the third which is planted between the two. The outer maxillae 

 are relatively large; they show a row of small bristles along the curved outer side, they have 

 the so-called olfactory orifices at the end of flat tubular processes, exactly as in the female and 

 just as already described by Darwin. 



The two pairs of limbs which represent the cirri have one ramus only. Darwin concluded 

 from the position of the excretory orifices (genital porus and anus) that these cirri answer to the 

 fifth and si.xth pair in other Cirripedes — but this view is not supported by the circumstance, 

 that I observed a rudimentary capsule in the basal segment of the first pair (in a small specimen 

 of 1,4 mm.), much resembling the so-called auditory sack. Hence I would conclude that the 

 first leg represented the first cirrus of an ordinary Cirriped. 



These legs vary much in size and are often represented by one- or two-jointed rudiments 

 only, either on one or on both sides of the same individual. I found them relatively large, 

 the first pair composed of 5, the second of 6 segments, in the 2,5 mm. long specimen which 

 accompanied the 3,5 mm. male of figure 3. In the largest of the two (the front part of which 

 is figured PI. V, fig. 4) the basal segment which according to Darwin represents the pedicel 

 of the cirrus, and which is beautifully pigmented with brownish purple, was very large in the 

 one cirrus as well as in the other. The anterior cirrus which was smaller than the posterior 

 and planted a little lower down on the thorax had four segments besides the basal one; the 

 posterior cirrus or leg had the same number, the terminal segment being moreover indistinctly 

 divided into two segments. Little brushes of spines are planted on the edges of the segments, 

 slightly more prominent towards the dorsal side. 



In the fig. 4 of PI. V I have indicated the free edge of the thorax as seen through the 

 basal segment of the last cirrus. Following that edge behind the last pair of cirri we see that 

 it forms a round excrescence ; a rather stout papillus, which projects freely at the so-called 

 dorsal side of the body. This papillus most probably represents the penis — I would say so 

 with greater emphasis, if I had been successful in discovering the genital porus at its surface 



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