642 A. E. Verrill — Turhellaria^ N^emertina, and 



length, long- elliptical, or sausage-shaped. Tentacular cirri long, 

 slender, tapered, acute, feebly articulated, about equal to the buccal 

 segment and head, and decidedly longer than the outer antennce. 

 Parapodia rather prominent and the segments rather deeply con- 

 stricted. Dorsal cirri long and slender, tapered ; the anterior ones 

 usually longer than the longest branchial cirri, and about equal to 

 the length of four bodj'-segments. 



Branchiae begin as simple cirri on the third segment ; become 

 trifid at about the Vth; 4-branched from about the 10th-14th to the 

 37th, and then decrease gradually, bifid and simple ones extending 

 nearly to the end, usually ceasing about on segments 100 to 105, 

 leaving about 40 bare, in specimens of average size. In the large 

 examples some of the larger branchiae may have five cirri ; their 

 cirri are long and slender, mostly subequal, arising from short stems, 

 so that the gill is digitate rather than pectinate ; the larger ones 

 meet across the back. 



The posterior and middle parapodia contain usually one or two 

 spiniform acicula and a rather smaller, oblique, recurved uncinate 

 one, which has a slightly bidentate tip, with two small scarcely 

 hooked terminal denticles, below which the inner edge bears a much 

 larger, rather wide, triangular tooth, standing at about right angles 

 to the shaft ; the end is broadly limbate. The compound setae have 

 rather long and narrow bidentate blades, the terminal hook being 

 narrow and but little incurved, the other a little removed and diverg- 

 ent, so that the interspace is concave ; the edge of the limbus and 

 the terminal inner edge of the shaft are finely denticulate, as in L. 

 elegans. The uncinate acicula fi'equently appear to have the tip 

 narrowly truncate, owing, perhaps, to the wearing away of the two 

 distal denticles, which are always smaller and less hooked than those 

 of L. hinominata. 



The color in life is milk-white or translucent white, often with 

 two submedian and two lateral rows of small, rou)id, blackish spots ; 

 the lateral spots are at the bases of the gills and occur in several 

 other species ; the other spots are often conspicuous, but are some- 

 times wanting in the ripe females, which have the whole posterior 

 part of the body filled with large white eggs. The intestine usually 

 shows as a broad, irregular brownish band, and the dorsal blood- 

 vessel as a narrow red line. 



Length of ordinary specimens, in life, 75 to 100™"" ; breadth, 

 l_2mm. jj^ formalin the length is usually about 60™™. A few females, 

 filled with eggs, are considerably larger, — about 100™"' long in 

 formalin. 



