493 
I have seen an Ammonite from Primrose Springs, South Australia, collected hy 
H. T. L. Brown, very closely allied to, if not identical with, this species.* 
Loc. Palmer Eiver {The'late Beo. J. E. T. Woods). 
Ammoitites walshensis, sp. nov., PI. 42, figs. 10 and 11. 
Bp. Char. Shell discoid, thin, much compressed ; whorls high, increasing very 
rapidly in size, the inner more or less concealed ; umbilicus narrow, moderately deep, 
and small for the size of the shell ; mouth sagittate ; back exceedingly sharp and without 
a defined keel ; fianks almost flat, having the slightest possible convexity, but imme- 
diately below the knife edge of the back slightly concave, surface with faint geniculate, 
or partially sigmoidal, delicate riblets, strongest around a line almost midway between 
the umbilicus and edge of the shell, and there producing a very slightly perceptible 
ridge ; between the riblets at this point are a series of wrinkles which assist in producing 
this median line, and breaking the general continuity of the flanks ; towards the perij)hery 
spiral lines are visible, but without causing any marked reticulation ; sutural characters 
Unknown . 
Ohs. In form this Ammonite resembles many Lower Mesozoic and Cretaceous 
forms. Its outline closely follows that of Ammonites {Amaltheus) lymensis, Wright, f 
but the ornament of the two shells is different. The spiral lines remind us of 
A. {Amaliheus) maryaritatus, Mont.,f but the cordate keel and large open umbilicus of 
the latter at once separate the two species. 
Amongst Cretaceous Ammonites, A. complanatns, Mantell, of the Grey Chalk, 
uaay be referred to. In form, but not wholly in structure, our species resembles 
A. clypeiformis, D’Orb.,§ from the Neocomian, but it is more compressed, and the former 
appears to be a plain shell with a moderately open umbilicus. In the small condition 
of this feature, and the sharp back, A. walshensis is brought into close contiguity with 
Ammonites requienianus, D’Orb.,|| which is very similar to the present species except 
for its closed and very small umbilicus. 
Referring again to A. complanatns, Mantell, If notwithstanding the great similarity 
lu shape to A. loalsltensis, including even the wrinkled median line on the flanks, there 
appears to bo an absence of the spiral lines, and with these is the remarkable peculiarity 
of a pin’s-point umbilicus, and a flat narrow back. 
My friend. Dr. Henry Woodward, to whom a photograph of this Ammonite was 
sent, suggests a comparison with Ammonites D’ Orb iyny anus, Geiuitz, but a figure of 
this shell is not accessible to me. 
Loc. Walsh Eiver {Hann’s Expedition — Queensland Mus.**) 
• Section— SCHLOENBACHIA. 
Ammonites inplattis, J. Sowerby, var., PL 34, figs. 1-4. 
Ammonites inflatus, J. Sowerby, Min. Con., 1817, ii., p. 170, t. 175. 
ji „ D’Orbigny, Pal. Frang. Terr. Cret., 1840, i., p. 304, t. 90. 
i> „ Stoliozka, Pal. Ind. (Cret. Ceph.), Ser. 3, 1861, Pt. i., p. 48, tt. 27, 28, 29, and 30, 
f. 1-3. 
Sp. Char. Shell discoid, sub-compressed, not greatly inflated, strongly carinate, 
Sour or five whorls visible, ovately quadrangular in section ; umbilical cavity freely 
* This has lately been de.scribed by Mr. W. H. Hudleston as A. fontinalis (Geol. Mag., 1890, 
(3), p. 241, t. 9, (. 1). 
t Mon. Lias. Ammonites, 1881, Pt. 4, t. 48, f. 1 and 2. 
t Ibid., 1882, Pt. 5, t. .93. 
§Pal. Fran?. Terr. Cret., i., p. 137, t. 42, f. 1 and 2. 
WIMd., p. 93. 
IT Sec Sharpe, Mon. Chalk Moll., Pt. i., 1853, t. 7, f. la and b. 
** Therefore probably collected by Mr. Norman Taylor, Geologist to the Expedition. 
