44 IOWA STUDIES IN NATURAL HISTORY 
Order Errantia: Carnivorous, free Polycheta with protrusible pharnyx, 
bearing jaws. Branchie generally on dorsal parapodia. 
Family Amphinomide: The body in this family is either vermiform, 
as in the genus Eurythe, or flattened, as in the genus Hermodice. 
The head bears a peculiar sense organ, called the dorsal ridge or 
‘‘earuncle,’’ which is a leaf-like process overlapping three or more 
segments. The parapodia bear gills. 
Hermodice carunculata Kingberg 
Plate V, Figs. 2 and 3; Plate VI, Figs. 3, 4, 5, and 6 
The largest speciment found is 230 mm. long and 20 mm. wide 
at its maximum breadth. It decreases posteriorly to about 5 
mm. at the anal segment. The body is a compressed quadran- 
gular shape in cross-section, flat ventrally and slightly arched 
dorsally. On the dorsal side the color is pale olive-green, shad- 
ing to gray laterally; while on the ventral side the color is a 
tan-gray, with a distinct bluish-black median stripe along the 
ventral groove. This stripe is not so evident in the young 
forms. The ecaruncle, located dorsally, is oval and extends 
posteriorly to the fifth segment. It consists of two rows of 
somewhat converging lamine, eight in number. From the 
anterior end projects the median unpaired palp, at each side of 
which are located two black eye-spots. The other four palpi 
are shorter. The first pair are located in front of the anterior 
pair of eyes and are at the anterior edge of the mouth eleva- 
tion. The more posterior pair are farther apart and are located 
at the sides of the second pair of eyes. The mouth is oval. The 
posterior circumference of the mouth opening is on the edge 
of the fourth segment of the ventral surface. The median parts 
of the fifth and sixth segments enter into the formation of a 
lip. There are two rows of parapodia, dorsal and ventral, 
separated from each other by a wide side-wall of the body. The 
ventral row is arranged in a straight line. The dorsal para- 
podia, on the other hand, are alternately drawn nearer the 
ventral ones. This outstanding peculiar characteristic makes 
them appear as a double row. Each of the ventral parapodia 
bears a wide fan-shaped bundle of sete with a small cirrus. 
There are two kinds of sete: the one rather wide and finely 
toothed along the coneave edge; the other with a sharp spur- 
like projection. The dorsal parapodia are larger. Each one 
