DESCUiniONb OK NKW 8()Uril WALES KOSSILS Kill Kl.'l ixiK. 187 



end-on the resemblance to the posterioi" end of a ConocardiiiDi, with itis 

 siphonal tube removed is sti-iking. 



In the present instance we are either dealing with a very remarkable 

 variety of M(y'onia nin'fiafa, or a quite new form. The difficulty of arriving 

 at a satisfactory conclusion on this point arises from the fact that examples 

 of .1/. rnn'iKtfd so seldom display the true outline of the species, but ai-e 

 usually met with as more or less crushed or distorted casts. 



I rel}- on the following features for the specific stability of this 

 shell : — (1) short form and gibbosity as compared with length ; (2) very 

 marked median cinctures ; (8) remarkably prominent cord-like diagonal 

 keels ; (4) markedly cordiform outline of the united posterior slopes. 



Loc. — Harper's Hill, near Allandale, West Maitland District (W. S. 

 Bun). 



Hor. — Permo- Carboniferous tufaceous sandstone of Lower Marine 

 Series. 



Mseonia carinata, Morris, vnr. minor, var. nov. 



(Plate xxix., tigs. 5-8.) 



Obs. — M(iiO)ua rariiutfa (s.s.) appears to be practically restricted to 

 the Upper Marine Series, for instance, as at Gerringong and Jamberoo in 

 the Illawarra District, and Bundanoon in the Berrima Laud District. 

 The peculiar and exaggerated form just described is, as previously stated, 

 from the Lower Marine Series at Harper's Hill, near Allandale Railway 

 Station, West Maitland District. 



The variety, or race represented in PI. xxix., figs. 5-8, is never of large 

 size, with an unmistakable tendency to " stumpiness," with prominent 

 diagonal ridges, approaching those of M. morrisii, but the flanks to all 

 intents and purposes in one plane, as in M. carimita, and not traversed by 

 wide, pronounced cinctures, similar to those in the former. 



It would be interesting to institute a comparison between this variety 

 and the original of a Mivonia from the Huon Road, Tasmania, referred by 

 Mr. R. M. Johnston to M. cariiuita,^^ with a slightly sigmoidal and out- 

 standing diagonal keel ; they are very much alike. 



Locs. — Bundanoon Gully, about one and a half miles from Bundanoon 

 Railway Station, Berrima Land District, New South Wales (W. W. TJiorpe). 



Hor. — Uppei" Marine Series. In the Lower Mai-ine Series at Farley 

 are casts of lesser size than PI. xxix., figs. 5-8, but possessing characters 

 of a very similar appearance. 



Mseonia morrisii, luir. (?) 



(Plate XXX., tigs. 1 and 2.) 



Ohx. — In this instance we are either dealing with a distinct species or 

 a variety of M. morrisii (PI. xxviii., figs. 7 and 8), notwithstanding the 



II Johnston — Systematic Ace. Geol. Tas., 1888, pi. xi., fig. 15a. 



