Scandinavian Phyllocarida. 147 
flexuous or zigzag ridge. They are six in number, blunt, and differ- 
ing much in size one from another; the middle of the body of the 
“tooth” is thicker than the ends. 
Two other specimens from the same locality have the cusps more 
distinctly arranged in two rows and somewhat alternating (Wood- 
cuts, Figs. 3 and 4). These in some respects approach fig. 21 in 
Barrande’s pl. 31. One of them is 17 mm., and the other (im- 
perfect ?) 10 mm. 
All the Scandinavian specimens of Crustacean teeth here men- 
tioned are from the Upper Silurian of the Isle of Faré, off the 
North-eastern extremity of Gothland. 
British specimens. —Fossil carapace-valves having irregular marks 
due to the presence of “teeth” within the squeezed valves of the 
carapace are not unusual in the collections from Lanarkshire. In 
the British Museum, “ No. 58878.” from Linburn, near Muirkirk, 
Lanarkshire, is a specimen showing a pair of “teeth,” each 8 mm. 
long, with six cusps, longer at one end of the “tooth” than the 
other (Woodeut, Fig. 7). Also another, “No. 45160,” figured in 
the Grou. Mac. 1865, PL XI. Fig. 2, from Lesmahago (Woodcut, 
Fig. 5). This measures 9 mm. long, and has an oblique basal 
portion, 10 mm. long. In the University Museum at Cambridge are 
two specimens. One of them, “0/11,” imperfect, with only four, 
rather long and irregular cusps (Woodcut, Fig. 7), is from Beck 
Mills, near Kendal (Upper-Ludlow Beds), and measures 6 mm. in 
length; and the other, ‘b/136,” from Lesmahago, Lanarkshire, has 
seven cusps, and is 12 mm. long, with an oblique root 15 mm. long ; 
the cusps are high and sharp at one end, and small and blunt at the 
other (Woodcut, Fig. 6). Referring to Gor. Mac. 1865, we see 
in Pl. XI. Fig. 1 (Ceratiocaris papilio, also from Lesmahago) that 
the ‘‘teeth” are made to appear as being opposed one to the other 
vertically (Woodeut, Fig. 9); this is, without doubt, due to the 
compression of the carapace, and to their being squeezed against the 
inside of the valves. In their normal position they would be opposed 
to each other horizontally, or nearly so. As regards the shape of 
these “teeth,” they resemble that of the others in the British 
Museum and those in the Cambridge Museum. In the Glasgow 
University Museum a fine example of C. stygia has similar teeth, 
also placed within the anterior portion of the carapace. All of 
these, however, have their cusps smaller and more regular than 
those in our Pl. VI. Fig. 10; they do not quite agree with our 
Fig. 8, which is probably allied to Barrande’s pl. 21, figs. 41-44 
(judging chiefly from the upper surface); and they differ much 
from our Pl. VI. Fig. 9. 
The specimens in the British Museum (Nos. 45160 and 58878), 
and the more perfect specimen of the two in the Cambridge Museum, 
differ materially from the Bohemian and Scandinavian specimens in 
the more trenchant character of their cutting edges, and in the broad 
elongated bases of attachment, suggesting that we may be here 
5 
dealing with two forms of masticatory organs,—namely, (1) a thicker 
