ho 
EXPLORATION OF ALASKA. OT 
ring, as well as in the centre of it around the vent, rather large conical 
tubercles 1.5 mm. in height; the branchial leaves, fifteen in number, 
as far as could be determined. 
The oral tube strong, 4.5 mm. long, wide. The bulbus pharyngeus 
about 5.5 mm. long, by a height of 3.0, and a breadth of 3.75 mm. ; 
the rasp-sheath about 1.75 mm., freely projecting, bent upwards. The 
cuticula of the lip-disk yellowish. The tongue with about thirty-five 
rows of plates (fig. 14-16) ; further backwards, twenty-five developed 
and four younger rows; the total number of rows sixty-four. On the 
posterior part of the tongue fourteen plates, the number increasing 
backwards to fifteen or sixteen. The five anterior rows very incom- 
plete, only represented by 1, 7, 9, 10, 12 plates (on each side). The 
plates as above. The breadth of the rhachis reaching to about 0.17 mm. 
The glandulx salivales 6.0 mm. long. The stomach (fig. 17a) about 
4.0 mm. long. The contents of the digestive cavity a mass of sponge. 
The vesiea fellea (fig. 17¢c) about 2.5 mm. high, with strong folds on 
the inside. The anterior genital mass quite as above, also the sper- 
matotheca and the spermatocysta (fig. 19), the penis (fig. 18, 20), and 
the vagina (fig. 18, 19). 
LAMELLIDORIS, Alder et Hancock. 
Lamellidoris, A. et H., Monogr. Brit. Nudibr. Moll., Part VII, 1855, p. xvii. 
Lamellidoris, A. et H., R. Bergh, Malacolog. Untersuch. (Semper, Philipp. 
Il, ii), Heft xiv, 1878, p. 608-615. 
Lamellidoris, A. et H., R. Bergh, Gatt. nérd. Doriden, 1. ¢., 1879, p. 
362-365. 
Corpus vix depressum, nothwo granulato. Branchia (non retracti- 
lis) e foliis (multis) simplicita pinnatis, ut plurimum in formam ferri 
equini dispositis, formata. Caput latum, semilunare, angulis tentacu- 
laribus. Aperture rhinophoriales, margine integro; tuberculis anticis 
2-5, calvitie postica. 
Cuticula aperture oralis infra asserculis duobus incrassata, et ante 
annulus papillarum angustus. Lingua rhachide lamellis humilibus in- 
structa; pleuris dente interno hamiformi permagno et externo com- 
presso lamelliformi unco minuto predito armatis. Ingluvies buccalis 
(suctoria) petiolo bulbo pharyngeo connata, tympaniformis. 
Penis apice (glande) curvatus, non armatus. Vagina brevis. 
The genus Lamellidoris was established (1855) by Alder and Han- 
cock, to receive two small groups of Doridid, one with the D. bilam- 
ellata as type, to which especially the name of the group is here 
