EXPLORATION OF ALASKA. 247 
The salivary glands deeply imbedded in the cavity for the oesophagus 
at the fore-end of the liver. The csophagus with its rather large 
(1.5 mm. long) diverticle, the stomach, the intestine with its little 
(1.0 mm. long) bag, as above. The liver 7.0 to 9.0 mm. long, 5.0 to 6.0 
mm. broad, 5.0 to 6.25 mm. high, of yellowish-gray color. The san- 
guineous gland of irregular, oval form, of a largest diameter of 4.0 
mm., by a thickness of 1.0 mm., and of grayish color. The renal syrinx 
about 0.75 mm. long. 
The anterior genital mass 6.0 or 7.0 mm. long, 4.0 to 6.0 mm. high, 
and 3.0 or 4.0 mm. thick. The ampulla as usual; also the (about 
40.0 mm. long) spermatoduct and the (nearly 2.0 mm. long) penis, 
with its armature; the hooks often set in pairs. The spermatotheca 
(diameter, 4.0 mm.) and the spermatocysta (diameter, 1.5 mm.) as 
above ; the chief duct, with the vagina (about 23.0 mm. long, by a 
diameter of 0.4 to 1.0 mm.), as usual, and also its internal cellular 
clothing (Pl. X, fig. 13); the yeliow nucleoli somewhat brighter; the 
cavity nearly filled with sperma. The mucous gland as usual. No 
black pigment on theginferior part of the vagina or on the penis. 
8. Acanthodoris pilosa (0. F. Miiller), var. purpurea, Pl. XII, fig. 1-9. 
Color e purpureo brunneus et flavescente-albidus, 
Habitat. Oceanum Pacificum septentrion. Insule Aleutiane (Una- 
lashka). 
Only two specimens of this species were dredged by Dall, in Sep- 
tember, 1874, on mud and stones, at a depth of about sixty fathoms. 
The color of the living animal was, according to Dall, “ purple-brown 
and yellowish-white.”” The length of the animals preserved in spirits 
was 24.0 or 25.0 mm., by a breadth of 9.0 or 10.0.mm., and a height 
of 7.5 mm.; the foot 6.0 mm. broad; the height of the rhinophoria 
about 3.0 mm., of the branchial leaves 2.3 mm. The color of the 
back reddish-brown ; the stalk of the rhinophoria brownish, the club 
yellowish ; the branchial leaves yellowish-white, the last brownish at 
the rhachis; the under side of the mantle margin, with the sides of 
the body, the head and the foot, yellowish-white, dotted with brownish- 
gray all over, the color much more scanty on the sides of the foot and 
still more so on the head and on the sole of the foot. 
The form was somewhat elongate. The back covered all over with 
pointed, rather (0.75 mm.) high, digitiform, soft papille and with inter 
mixed smaller ones. The margin of the rhinophor-holes with several 
pointed, projecting, digitiform processes; the stout club of the rhino- 
