LEODICID^ OF THE WEST INDIAN REGION. 125 



part of one side. There are two basal pieces joined at their posterior ends and with large 

 teeth along the inner edge (only one is drawn). At the end of this basal piece a double 

 row of plates begins. The upper row is made up of larger plates, each with a central bent 

 tooth, and on either side a smaller denticulation. Only six of these are figured. Below 

 this row is a row of smaller plates with rather smaller teeth. Beyond the sixth plate the 

 upper plates are not drawn, the lower ones being the only ones shown. Toward the 

 outer end they gradually become more slender, their lateral teeth become more numerous 

 and smaller, and they may become bifid at the end. Text-figure 457 is drawn from one 

 of these from a Bermuda specimen, and this is rather stouter than any I found in the one 

 from Tortugas. The Tortugas specimen had about forty plates in each row. Lateral to 

 these rows of plates, on either side, are two rows of smaller plates, differing from them 

 mainly in size. The mandible (text-figure 458), from a Bermuda specimen, is slender and 

 with the anterior edge lobulated, but not continued in rows of smaller plates. 



One specimen was collected by dredging in the Northwest Channel and one to the 

 south of Loggerhead Key at the Tortugas, in 1913 and 1915, respectively, and one in 

 Ely's Harbor, Bermuda, in 1916. 



Stauronereis melanops Verrill. 



(Text-figures 459 to 467.) 

 Stauronereis melanops Verrill, 1900, p. 648. 



Length of body in preserved material about 20 mm. The prostomium width is 

 1 mm., the greatest body-width not over 2 mm. 



The prostomium (te.xt-figure 459) is uniformly rounded and a trifle wider than long. 

 Verrill states that "a pair of divergent narrow-lanceolate ridges arises from the middle of 

 the posterior margin." This I understand to be the structure figured, but which I 

 should describe as a pointed elevation who.se apex is at the middle of the posterior 

 margin of the prostomium and whose margins diverge to end just behind the bases of the 

 tentacles. The posterior pair of eyes lie just lateral to the sides of this elevation. The 

 anterior eyes are much larger than the posterior and are largely concealed by the bases 

 of the tentacles. The tentacles are longer than the width of the prostomium, are very 

 obscurely articulated at the bases, but sharply so toward their ends. Verrill states 

 that they have tliirteen articulations. I was unable to determine the precise number 

 on the material at my disposal, as it is difficult in preserved animals to distinguish 

 articulations from wrinklings. The palps are much larger than the tentacles, not 

 quite so long, and more or less wrinkled. 



The first somite is divided on the dorsal surface by a ridge which runs transversely, 

 separating a narrow anterior portion from the remainder. This anterior portion is 

 broadest just behind the apex of the prostomial ridge, and narrows to a point on either 

 margin of the body. Laterally the peristomium sends forward a heavy lobe on either 

 side, which is separated from the prostomium by a depression. This is not continued 

 onto the ventral surface. There are heavy, pad-like lips. The second somite is about 

 as long as the peristomium, and succeeding ones increase very slightly in length. The 

 greatest body-width is about at the middle, from which it tapers about equally in the 

 two directions. Most of the anterior somites show a transverse ridge which may be a 

 preservation effect. On preserved material there is a ventro-median row of brown spots, 

 one to a somite. The terminal portion was not well preserved, but there were two pairs 

 of anal cirri, one pair much larger than the other. 



The first parapodium (text-figure 460) has a setal lobe whose margin curves upward 

 to a conical angle. There is a conical posterior lip and a rather heavy ventral cirrus, 

 with a rounded apex and somewhat longer than the setal lobe. There is no dorsal cirrus. 



