EXPLORATION OF ALASKA. Fils 
the foremost, with rather ovtuse point (fig. 9). The buccal crop (fig. 
4, 5) as large as the bulbus, of quite the usual form, rather petiolate.! 
The salivary glands forming (on each side) a large, thick, whitish 
mass between the bulbus and the central nervous system (with the 
glandulew sanguine). 
The cesophagus rather wide. The stomach and the intestine as 
usual. The liver as usual, much flattened on the right anterior half. 
The heart rather large. The gland. sanguinez large, whitish, cover- 
ing the upper side of the central nervous system, the foremost part in one 
individual very narrow. The renal syrinx about 1.0 mm. lon 
strong longitudinal folds, its clothing as usual. 
The anterior genital mass 4—4.5 mm. long by a breadth of 1.25-1.5 
and a height of 3-3.3 mm., yellow-white, plano-convex ; the anterior, 
g, with 
and partly the superior portion formed by the coils of the whitish sper- 
matoduct ; in one individual one coil embraced the sheath of the radula. 
The first part of the spermatoduct strong, when unrolled about 25.0 mm. 
long; the succeeding part of the length of 45.0 mm., thinner; the 
rest about 7.0 mm. in length, stronger, nearly as in the first part. In 
the. beginning of this last part the true spermatic duct was rolled up in 
tight coils, the remaining part of its length was nearly straight. The 
penis about 1.5 mm. long, with the usual glans in the interior. The 
spermatotheca (fig. 6a) spherical, its chief duct nearly twice as long as 
the bag, the vagina short (fig. 6¢). The spermatocysta appeared 
pyriform (fig. 6d). 
In color this form seems to differ from the typical one, as that is 
represented by Alder and Hancock (Monogr., Part vi, 1854, fam. 3, 
Pl. 9); in the anatomical relations no specific differences could be 
detected. . 
A specimen of another variety was obtained by Dall, on a gravel 
beach, at low water, in June, 1874, at Port Etches (Prince William 
Sound’. According to Dall, the mantle was of ‘‘ brown” color. 
The specimen had a length of 13.0 mm., by a breadth of 8.0 mm., 
and a height of 5.0 mm.; the height of the leaves of the gill was 
about 1.0 mm. The color of the back was brownish and yellowish; 
that of the gill, as well as of the rhinophoria, yellowish. The number 
of leaves of the gill was about thirty. 
The bulbus pharyngeus about 1.75 mm. long, by a height of 1.5 mm. ; 
the sheath of the radula nearly as long as the bulbus; the buccal crop 
1 In one specimen the form of this organ was entirely as figured in my 
Malacolog. Untersuch. (Semper, Reisen). Tab. LXV, fig. 2. 
