LOWER PALAEOZOIC HYOLITHID^ FROM GIRVAN. 



219 



Horizon and Locality. — Balclatcliie Group, Balclatchie. 



Remarks. — The simplicity of the lobation of this small shell distinguishes it from 

 Pt. girvanensis, and it does not seem possible to regard it as merely the young of that 

 species. It more resembles the Bohemian species, Pt. bohemica, Barr.* The 

 American species, Pt. expansa (Emmons),t may also be compared. 



List of Species. 



Hyolithes ardmillanensis, sp. nov. 



,, asteroideus, sp. nov. 



„ candidus, sp. nov. 



., columbanus, sp. nov. 



„ girvanensis, sp. nov. 



,, immemor, sp. nov, 



„ multipunctatus, sp. nov. 



,, penkillensis, sp. nov. 



,, subcrispatus, sp. nov. 



,, sylvestris, sp. nov. 



,, sp. ind. (a). 



., sp. ind. (f3). 



„ sp. ind. (y). 



Hyolithes (Orthotheca) subexcavatus, sp. nov. 



,, ,, subornatus, sp. nov. 



„ ,, thraivensis, sp. nov. 



,, ,, „ var. granuliferus. 



1 sp. ind. 

 Ceratotheca 1 subuncata, sp. nov. 



„ 1 balclatchiensis, sp. nov. 



Pterotheca drummuckensis, sp. nov. 



,, girvanensis, sp. nov. 



,, mullochensis, sp. nov. 



,, multidecorata, sp. nov. 



„ simplex, sp. nov. 



Craighead Limestone — 

 Hyolithes, sp. ind. (y). 



Balclatchie Group — 



Hyolithes ardmillanensis. 



„ girvanensis. 



„ immemor. 



„ multipunctatus. 



„ (Orthotheca) subexcavatus. 

 Ceratotheca 1 balclatchiensis. 

 Pterotheca girvanensis. 



„ simplex. 



Whitehouse Group — 



Hyolithes candidus. 



,, (Orthotheca) subornatus. 



Drummuck Group — 



Hyolithes asteroideus. 

 „ columbanus. 



* Barrande, op. cit., p. 104, pi. xv. figs. 1-6. . 

 t Emmons, Geol. Rep. 2nd Distr. New York, 

 Pakeont. iii. (1902), p. 179, pi. xii. fig. 35. 



TRANS. ROY. SOC. EDIN., VOL. XLVII. 



Stratigraphical Distribution of the Species. 



Drummuck Group — continued. 



var. granuliferus. 



Hyolithes subcrispatus. 



„ (Orthotheca) thraivensis. 



>; >) ii 



Pterotheca drummuckensis. 



Mulloch Hill Group — 



Hyolithes, sp. ind. (/3). 

 Pterotheca mullochensis. 



Saugh Hill Group — 



Hyolithes sylvestris. 



,, sp. ind. (a). 

 ? Pterotheca mullochensis. 



Penkill Group — 



Hyolithes penkillensis. 



„ (Orthotheca 1) sp. ind. 

 Ceratotheca 1 subuncata. 

 Pterotheca multidecorata. 



1842, p. 397, figs. 109-112 ; Weller, Geol. Sun. New Jersey, 

 PART II. (NO. 9). 32 



