Leptochiton asellus, Spengler. 
Chiton asellus, Spengler, Skriv. Nat. Selsk., vol. 4, 1797, p. 99. 
Forbes & Hanley, Brit. Moll., vol. 
1853, p. 407, Pl. 59, fig. 1, 2, Pl. AA, fig. 5. 
— cinereus, Jeffreys, Brit. Conch., vol. 3, 1865, p. 218, vol. 5, p. 198, Pl. 56, fig. 2. 
Lepidopleurus cinereus, G. O. Sars, Moll. Reg. Arct. Norv., 1878, p. 112, Pl. 7, fig. 8a—h. 
Leptochiton 
Lepidopleurus =— 
Chiton cinereus, Linné, har af flere forfattere, saasom 
Jeffreys og G. O. Sars, været henført til chiton asellus, 
Spengler, medens andre, saasom Forbes & Hanley, Dall 
og Tryon, som det synes os, med større ret har anseet den 
for identisk med chiton marginatus, Pennant. For at und- 
gaa confusion har vi ikke villet benytte Linnés artsnavn, 
men istedet foretrukket at bruge Spenglers og Pennants for 
disse to arter. 
Leptochiton asellus fandtes ved Husø og Bodø. Den 
er en af vore mest almindelige arter. Mod nord gaar den 
til Kvænangen (70° n. br.), hvor Sparre Schneider bar 
taget et lidet exemplar. Arten er udbredt langs Vest- 
europas kyster fra Island til Spanien. I Kattegat gaar 
den ned til Belterne. Den bathymetriske udbredelse er 
Q—150 fy. Fossil er den kjendt fra Norge, Skotland og 
Sicilien. 
asellus, Dall, Proc. U. S. Nat. Museum, vol. 1, 1878, p. 318. 
Tryon, Man. of Conch., vol. 14, 1892, p. 8, Pl. 3, fig. 64—66. 
Chiton cinereus, Linnæus, has been referred by several 
writers — e. g. Jeffreys and G. O. Sars — to Chiton 
asellus, Spengler, while others — e. g. Forbes & Hanley, 
Dall, and Tryon — have, as seems to us with more justi- 
fication, considered it te be identical with Chiton margi- 
natus, Pennant. In order to avoid confusion, we have 
refrained from using Linnæus specific name, and have 
preferred in stead to employ Spengler’s and Pennant's for 
these two species. 
Leptochiton asellus was found at Husø and Bodø. 
lt is one of the most common Norwegian species. It ex- 
tends north-wards as far as Kvænangen (70° N. Lat.), 
where Sparre Schneider found one small specimen. The 
species is distributed along the shores of Western Hurope, 
from Iceland to Spain. In the Kattegat it extends south- 
wards as far as the Belts. Its bathymetrical distribution 
is from 0 to 150 fathoms. It occurs as a fossil in Nor- 
way, Scotland, and Sicily. 
Trachydermon exaratus, G. O. Sars. 
exaratus, G. ©. Sars, Moll. Reg. Aret. Nory., 1878, p. 118, På. 8, fie 1La—k, Pl Il, fie. 1. 
Lophyrus 
Trachydermon = — Verrill, Trans. Connecticut Acad., vol. 6, 1884, p. 208, Pl. 30, fig. 2. 
Ischnochiton — Tryon, Man. of Conch., vol. 14, 1892; p. 71, Pl. 7, fig. 39—49. 
Denne art foreligger kun fra station 255 (Vestfjorden), 
341 fy. Den er tidligere kun funden sparsomt langs Nor- 
ges vestkyst fra Bergen til Lofoten samt ved Nordamerikas 
østkyst (Marthas Vineyard og Florida). Den bathymetriske 
udbredelse er 100—341 fy. 
This species was only found at Station 255 (West 
Fjord, 341 fathoms). Previously it had only been found 
in small numbers along the west coast of Norway, from 
Bergen to Lofoten, and off the east coast of North Ame- 
rica (Martha’s Vineyard and Florida). Its bathymetrical 
distribution is from 100 to 341 fathoms. 
Trachydermon albus, Linné. 
Chiton albus, Linné, Syst. Nat., ed. 12, 1766, p. 1107. 
— — Jeffreys, Brit. Conch., vol. 3, 1865, p. 220, vol. 5, p. 199, Pl. 56, fig. 3. 
Lophyrus — G. 0. Sars, Moll. Reg. Arct. Norv., 1878, p. 114, Pl. 8, fig. 2a—h, Pl. I, fig. 9. 
Trachydermon — Dall. Proc. U. S. Nat. Museum, vol. 1, 1878, p. 322. 
Ischnochiton — Tryon, Man. of Conch., vol. 14, 1892. p. 70, Pl. 7, fig. 35—38. 
Findested. Saltstrømmen, Tromsø 30—40 fy., Alten 
30 fr., Hammerfest 20 fv., Jan Mayen 20—30, Advent Bay 
20 fy., station 195, 107 fv. og station 270, 136 fy. 
Locality. Saltstrømmen, Tromsø (30—40 fathoms), 
Alten (30 fathoms), Hammerfest (20 fathoms), Jan Mayen 
(20—30 fathoms), Advent Bay (20 fathoms), and Stations 
195 (107 fathoms) and 270 (136 fathoms). 
