32 Annelida Chcetopoda 
lobes, upper and lower. Lower lingula, similar to upper, 
but shorter ; after the first few segments projecting a little 
beyond the lower ramus. 
Dorsal cirri, delicate, conical, not quite reaching the end 
of the upper lingula. 
Ventral cirri, similar to dorsal cirri, but shorter ; they 
arise below (within) the base of the lower lingula from a 
slight elevation, and reach about to the middle of the lower 
lingula. Further back the upper lip of the dorsal ramus 
becomes smaller and finally disappears. The posterior lip 
of the ventral ramus also disappears, and the terminal 
division of the anterior lip into lobes becomes less marked. 
The ventral cirri shorten and recede from the lower lingula, 
while the feet have their basal portion much elongated. 
Setae, all of one kind on the anterior feet (f. 63). Ap- 
pendix slender, acute, edge beset with numerous short 
hairs. Terminal points of stem in the same plane [Aretes 
homogomphes Clpd.). They are arranged in three bundles, 
one in the dorsal ramus, two in the ventral. Ventral setse 
very numerous and crowded. Falcate setse (f. 64) occur 
first between the 30th and 40th segments ; at first in the 
lower bundle, few in number ; becoming more numerous, 
they occur also in the upper bundle of the lower ramus, 
bnt never entirely replace the first form, and disappear 
again in the posterior segments. 
Proboscis (f. 57) about twice the length of the head. 
Paragnathi, i, fail; ii, 6 to 10 in small bunches; iii, 2 
or 3 irregular transverse rows ; iv, 10 to 12 in bunches. 
All black, small, conical, the inferior (iii), smallest; v, vi, 
vii, viii, fail. 
Jaws, usually light horn color, with dark brown or black 
edges and tips; curved, twisted externally; denticles 
small, number variable. In the dorsal ramus there is 
