LEODICID^E OF THE WEST INDIAN REGION. 117 



slsts throughout the body. Beginning with the peristomium, each somite has numerous 

 small light-yellow spots on its dorsal surface with a row of larger spots running across 

 each somite a little in front of its median line. These never form a straight line, but 

 are more or less zigzag in arrangement, though they never form two rows. The spots 

 gradually become indistinct and finally disappear in the region of the twenty-fifth 

 somite. An animal of average length was 150 mm. long with a peristomial width of 1.5 

 mm.; it had about 200 somites. 



The prostomium (plate 7, figure 14) is rounded, with a very faint notch on its 

 anterior border, and is colorless except for a patch of scattered yellowish-brown dots 

 between the tentacles and the anterior border of the peristomium and a prominent yellow- 

 brown patch antero- ventral to each eye. One pair of large, dark eyes, situated toward the 

 lateral margin, and a much smaller pair near the middle line. These are often concealed 

 by the tentacles when the anterior end of the body is expanded and when it is contracted 

 they, as well as the tentacles, are covered by the anterior border of the peristomium. 

 There are three tentacles approximately equal in size, which are entirely covered by the 

 anterior border of the peristomium when the animal is contracted. Behind them are 

 rounded lobes, not often protruded beyond the peristomial border. When undisturbed 

 the prostomium is usually bent downward so that the tentacles are exposed. They 

 usually extend straight up into the water instead of lying parallel with the prostomial 

 surface (plate 7, figure 13). 



The peristomium (plate 7, figure 14) is about as long as the two following somites. 

 It is biannular ventrally, though not dorsally, and may represent two somites. The 

 later somites increase noticeably in width to about the middle of the body, and from 

 there backward the diameter diminishes, narrowing very abruptly at the posterior end. 

 There are two pairs of stout anal cirri (plate 7, figure 16). 



The first parapodium (text-figure 429) has a pointed post-setal lobe, a foliaceous 

 dorsal cirrus, and a large oval ventral one. In the tenth parapodium (text-figure 430) 

 the foliaceous character of the dorsal cirrus is more marked and the ventral cirrus is 

 still more prominent, though it remains rounded and does not flatten, as do the dorsal 

 ones. Parapodia from the middle and posterior regions of the body show this character 

 of the dorsal cirrus even more markedly than anteriorly, and the ventral cirri are also 

 very prominent throughout the body (plate 7, figure 15). Needle aciculse occur in all 

 dorsal cirri, and the post-setal lobes are long and conical (text-figure 431). 



The seta3 lie in a single vertical row between the setal lobes. The dorsalmost are 

 the longest. They are slender, more or less curved, and without any lateral wing. 

 Ventral to these are shorter ones which are gently curved and with a small wing along 

 the margin. Toward the anterior end of the body two aciculse are in each parapodium, 

 and between somites 20 and 30 a ventral acicula makes its appearance. This (text- 

 figure 432) tapers gradually to the bifid apex, which is covered by a small hood. 



The maxilla (text-figure 433) has very long and slender bases on the carrier and the 

 parts are strictly symmetrical. The first or forceps-plate on either side is attached to 

 the carrier, its proximal portion is almost rectangular, with the inner margin produced 

 into a row of 7 distinct teeth, with smaller denticulations posterior to them. The terminal 

 portion of each forceps-plate is drawn out into a much-curved, sharp-pointed hook. 

 The three following pairs of plates are successively smaller, but similar to one another in 

 form. Each has a terminal large tooth, followed by a small one, then 2 large ones, and 

 finally 2 very small ones. In the fifth pair each has only 1 tooth. Lateral to the plates, 

 on either side, are 3 light-brown accessory plates. The mandible (text-figure 434, 

 drawn from another specimen and on a smaller scale than the maxilla) has rather slender 

 shafts, with the terminal beveled portion set at an angle of 45 with the shaft. This 

 portion has a colorless extension on its outer angle. 



