L/ETMATONICE PRODUCTA. 263 



touching the base of the lateral cephalic swelling. It appears to be the rudiment of a 

 scale-bearing process. The ridge from which the tentacle arises extends backwards in 

 the middle line, and at the posterior border of the head it bends outward on each side 

 to bear the papilla, viz., the modified scale-bearing process. The papilla? of the facial 

 tubercle are more lobate than in L. producta from Kerguelen, and proportionally less 

 elongate. The palpi are, so far as the specimens go, less powerful than in L. producta 

 from Kerguelen, but the difference in regard to the papilla? or spikes is small. Both 

 have numerous papillae as in L. filicomis. All that can be said is that perhaps they are a 

 little more numerous towards the tip of the palpi of L. producta from Kerguelen. The 

 tentacular cirri are somewhat longer than the tentacle, and their tips are rather more 

 elongate than in L. filicomis, while they are shorter than in L. producta from Kerguelen. 



The segmental papilla? begin on the posterior face of the fifth foot, and extend to the 

 thirty-eighth. They form flattened processes somewhat more distinct than in L. producta 

 from Kerguelen. Besides, in the latter form they begin on the tenth foot, and extend to 

 the thirty-ninth. 



The papilla? of the proboscis (Plate XXXVII, fig. 3) have broader tips than those of 

 L. filicomis, and are less regularly dichotomous. The tips are sometimes divided into 

 three, and occasionally are ovate, clavate, or irregularly lobate. There is not much 

 ground for calling the thickened regions of this organ parts representing maxilla?, as 

 Grube does. 



No specimen is in a condition to give a reliable opinion of the arrangement of the 

 dorsal spines. The papilla? bearing them are a little more prominent than in L. producta 

 from Kerguelen, but this may be due to their condition, for they have evidently been 

 subjected to considerable hardships. They probably spread, in the scale-bearing feet, 

 over the dorsum as in the forms from Kerguelen, the feet carrying cirri having dense 

 groups of more slender bristles. 



The structure of the first two feet agrees with that in the form from Kerguelen. 

 The other feet are also similar in structure. The tips of such of the long dorsal spines 

 as were present agreed with the figure (Plate XXXVI, fig. 4), which shows a spine 

 slightly turned to the left, four recurved fangs occurring on each side, besides the point 

 at the base of the spear-like tip. The ventral bristles (Plate XXXVI, fig. 5) conform 

 mostly to the type of L. producta, var. Wyvillei, having somewhat stiffer (stouter) basal 

 bristles and numerous slender distal ones. 



In describing this form in the Annelids of the ' Challenger,' I for some time had the 

 varieties ranged under separate species, distinguished by certain evident characters. 



The reticulate cordate structure of the scales is very well marked (apparently better 

 than in any other species), forming a series of wavy lines like those on the sand of the 

 sea-shore. 



No parasitic Loxosoma? occur on this form, yet foreign varieties abound with them, 

 such as L. producta, var. benthaliana, on which the remarkable new gymnoblastic 

 hydroid, Stylactis vermicola, described by Prof. Allman, occurs on the under surface of 

 the scales of this inhabitant of the depths (2900 fathoms) of the North Pacific. 



The species was first procured by Prof. Haddon during the Royal Dublin Society's 

 Survey, on a bottom of sand and gravel at a depth of 500 fathoms, fifty-four miles off 



35 



