PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 385 
broad, vertical notch. Reproductive organs large and prominent; the 
two aes are situated on a large tubercle in front of the gill. The 
male organ, in extension, is long, slender, usually curled, trincate, about 
equal in length to half ie breadth of the body; it is a tubular organ, 
with a slit along the lower side, formed by the rolling up of a long, da 
‘membranous process. At the posterior edge of the tubercle there is a 
shorter, flat-pointed process, connected with the female organs. Color 
of dorsal surface yellowish brown, lighter or darker, and reticulated 
with dark brown, often specked with flake-white; gill and proboscis 
dark purplish brown; the proboscis with a darker dorsal patch; tenta- 
cles sometimes crossed by dark brown bands. Foot salmon-color. 
Odontophore very large and broad, with 150 to 170 rows of teeth; no 
median teeth; all the teeth are similar in structure, and show only a 
gradual change in form and size from the inner to the outer ones. The 
inner ones are elongated, slightly curved, narrow-lanceolate, with a very 
acute point and with a smaller, narrow, sharp denticle on the inner 
edge, parallel to but shorter than the main point; the outer teeth grad- 
ually become shorter, blunter, with a smaller denticle, which finally 
nearly disappears. Length, usually 30" to 40"; breadth, 10™™ to 14". 
About 20 miles south of Block Island (stations 814 to 817), in 38 
fathoms; about 70 to 74 miles south of Martha’s Vineyard (stations 865 
to 872), in 65 to 192 fathoms, fine, compact sand, very abundant (140 
specimens). Also 90 to 100 miles south of Newport, R. I., in 85 to 225 
fathoms (stations 873 to°879). “Closely resembles Pleurobrancheca Nove- 
Zealandie in form and color. The latter is a littoral species. 
Dendronotus elegans Verrill, sp. nov. 
Form and general appearance nearly as in D. arborescens, but rather 
more slender. Branchize with rather longer stems and less numerous 
branches than in the latter, but similarly arranged. Tentacle sheaths 
with the terminal lobes not so finely divided, and with a smaller branch 
on the outer side, near the base. Frontal processes of the head numer- 
ous, large, with elongated stems, and not so much branched as in D. 
arborescens. Color everywhere nearly uniform pale salmon; tentacles 
more yellowish. The dentition is peculiar and distinguishes it easily 
from both our other species. Median tooth stout, smooth, entirely desti- 
tute of lateral denticles; its free portion, in a dorsal view, is broad-trian- 
gular, almost as broad as long, acute at tip; base transversely elliptical, 
a little broader than the free portion. Lateral teeth about ten on each 
side, slender, the outer two or three shorter, blunt or subacute; the 
others are successively longer and larger, and each has a more acute and 
more oblique tip than those that precede it, except the inner one, which 
has a shorter tip, with longer spinules. These lateral teeth are rather 
suddenly curved inward where they begin to taper, and beyond the curve 
the tip becomes nearly straight again, and very acute, while the anterior 
edge of the carvature is covered with slender, sharp spinules. 
Proc. Nat. Mus. 80 29 Dec. 23, 18890. 
