462 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxxv. 



This neck carries on either side close to the head a stout horn some- 

 what longer than those on the side of the head and not quite as stilt' 

 and hard. Each of these horns is slightly enlarged at its tip, where 

 it gives off three or four small knobs or branches. About halfway 

 between these second horns and the genital segment is a third set, 

 four in number, one on either side and a pair close together on the 

 ventral surface. These are all very hard and chitinous, the two 

 lateral ones a little longer than the. second pair, the ventral ones con- 

 siderably shorter, and all four profusely branched. The ventral pair 

 are so close together that their bases are partly fused and at first 

 glance they might easily be mistaken for a single horn; but a little 

 examination shows them to be unmistakably a pair placed close 

 together. 



The genital segment enlarges abruptly from the base of the neck 

 to fully five times the diameter of the latter. It is cylindrical, 

 slightly enlarged posteriorly, a little curved, and smoothly rounded, 

 without appendages of any sort, but with a small rudimentary lobe 

 over the base of each egg string. The abdomen is also small and 

 rudimentary, little morje than a knob or lobe projecting slightly 

 from the dorsal surface of the posterior margin between the egg 

 strings. It is notched at the center, indicating the position of the 

 anus, but carries no anal lamina? or seta\ The egg strings are about 

 the same diameter as the narrowest part of the neck, and very long, 

 but they are coiled in a tight spiral of about three times their own 

 diameter, and thus actually project behind the genital segment a 

 distance less than the length of the body. If straightened out, how- 

 ever, they would prove to be more than twice that length. The 

 eggs are small and uniseriate, and each string contains between 1,200 

 and 1,500. 



The mouth is terminal and is surrounded by mouth parts so degen- 

 erate that they have become mere spherical knobs. There are two 

 pairs of these close together and close to the mouth and another 

 pair at a little distance from them on the ventral surface. This 

 last pair is somewhat asymmetrical in their position, being twisted 

 around to the left side, but otherwise are exactly like the first two 

 pairs. 



The only other appendages visible are two pairs of rudimentary 

 legs close together on the ventral surface about halfway between the 

 lateral horns on the head and the first pair on the side of the neck. 

 These legs arc very short and slender, uniramose. three-jointed, and 

 destitute of spines or seta?. 



Total length, including egg strings, 30 mm. Length of head and 

 neck', !) nun.; of genital segment, 8 mm.; of egg strings, 14 mm. 

 Width of genital segment, 3 mm.; of the egg-tube coils, 1.12 mm. 



