SEHIONOTIDiE. 
61 
An elongated species, attaining a length of about 015; the 
depth of the caudal pedicle nearly equalling half the maximum 
depth of the abdominal region. Length of head with opercular 
apparatus slightly less than the maximum depth of the trunk, and 
contained five times in the total length of the fish; external hones 
coarsely rugose. Pelvic fins relatively large, nearer to the anal 
than to the pectorals; dorsal fin arising behind the origin of the 
pelvic pair, about as deep as long, and the anal arising opposite its 
hinder extremity. Scales smooth, scarcely deeper than broad upon 
the flank. 
Form. Sf Log. Bunter Sandstone : Wasselnheim, Alsace. 
Not represented in the Collection. 
Semionotus tenuis, A. S. Woodward. 
1890. Semionotus tenuis, A. S. Woodward, Mem. Geol. Surv. N. S. 
Whales, Pakeont. no. 4, p. 31, pi. vi. fig. 3. S . cu— 
Type. Imperfect fish; Geological Survey Museum, Sydney. 
An elongated species, attaining a length of about 0*13; caudal 
pedicle slender, its depth contained two-and-a-half times in the 
maximum depth of the abdominal region. Length of head with 
opercular apparatus not less than the maximum depth of the trunk, 
and equalling somewhat more than one-fifth of the total length of 
the fish. Pin-fulcra large and very slender; dorsal fin arising 
about the middle of the back, the length of the first ray equalling 
the depth of the trunk at its insertion ; anal fin arising opposite 
the hinder extremity of the dorsal. Scales smooth, those of part 
of the flank twice as deep as broad. 
Form . Toe. Lower Hawkesbury-Wianamatta Series (Upper 
Trias) : Gosford, New South Wales. 
Not represented in the Collection. 
The following specimens are not specifically determined :— 
38659. Imperfect head and abdominal region of a comparatively 
large and elongated fish with smooth scales; Keuper, 
Stuttgart. Purchased , 1864. 
P. 1546. Slab with imperfect remains of three small fishes ; Keuper, 
Coburg. Egerton Coli. 
The following species of Semionotus , all from Europe except the 
first, have been founded upon specimens which are mostly fragmentary 
and are not represented in the Collection :— 
Semionotus australis, A. S. Woodward, Mem. Geol. Surv. N. S. 
Wales, Palaeont. no. 4 (1890), p. 31, pi. vi. fig. 2.— 
