236 RECORDS OP THE AUSTRALIAN MUSEUM. 



Ammonite* inflatus, Stoliczka, Foss. Ceph. Cret. Rocks S. India 

 (Pal. Ind.), i., ser. 3, pt. 1, 1863, p. 48, pi. xxvii.,pl. xxviii., 

 pi. xxix., pi. xxx., figs. 1-3. 



Ammonites (Schlmibachia) inflatus, Eth. til., Geol. Pal. Q'land, 

 &c, 1892, p. 493, pi. xxxiv., tigs. 1-4, (?) pi. xlii., tig. 12. 



Sp. Chars. — Shell large, discoid ; whorls numerous (precise 

 number unknown) ; venter variable, narrow or broad according 

 to age, broad in young examples, narrower in more mature and 

 aged individuals ; keel more prominent and sharper in older than 

 in younger shells, the surface of the venter always channelled on 

 each side the keel ; abdominal angles defined by lines of huge 

 tubercles varying in character according to position, and always 

 hidden by the embracement of the whorls ; dorsum correspond- 

 ing in width to the venter, with a u-shaped impressed zone, in 

 the young sharply angular but in older individuals wider and 

 shallower ; flanks flat to depressed convex ; umbilical cavity wide 

 and open exposing all the whorls ; section variable, according to 

 age, but always higher than wide, and in strict outline octagonal ; 

 costse on the older and smaller whorls gracefully sigmoidal and 

 usually bifid at about the middle of the flanks, but in aged 

 examples this bifurcation ceases and the costa: are all single, 

 long and short alternately ; tubercles in two or three lines, or 

 rows, on each side of the keel, one row abdominal in position, the 

 other supra-umbilical, and if a third be present it is mid-lateral ; 

 all increase in size with age, the abdominal in the uerontic 

 condition are large, conical and pointed ; spiral lyrse also occur 

 on middle-aged shells, roughening the costa', but faint in the 

 valleys, and crenulating the abdominal rows of tubercles, also 

 visible in the ventral channels. 



Obs. — Although known as an Australian species I am induced 

 to figure the accompanying specimens as indicative of size and 

 confirmatory of the previous determination. The mouth has not 

 been observed in an Australian specimen and the rostrum only 

 doubtfully so. The variation in size and form of the tubercles is 

 remarkable ; where crossed by the spiral lyrse they are more 

 expanded and blunter as compared with the conical projections 

 of other parts of the shell. 



The section, inclusive of the dorsal groove, is octagonal in the 

 smaller and younger whorls, but longitudinally elongated in 

 consequence of the projection of the keel ; the embracement of 

 the whorls always conceals the abdominal row of tubercles. 



