APPENDIX. 



BESCRIPTIONS OF THE NEW SPECIES OF FOSSILS 

 FROM THE ANTALO LIMESTONE. 



Hemicidaris Abyssinica, sp. iiov., fig. 1. 



Testa depresso-glohosa, vel sphceroidea, vel suhtus plana, supra fere hemi- 

 sphcerica. Arece anibulacrales subrectw, strictm, tuherculis parvis, 

 suboequalibus, vix superne niinoribus,fere cequidistantihus hiseriatim 

 alternantibus et granulis irregulariter interspersis ornatce. Arece 

 interamhulacrales seriebus duobus 8-9 tvherculorum majorum in- 

 structce tuberculis utrinque granulis circumdatis, aliis granulis 

 minoribus scepe irregulariter ad margines laminarum interjectis ; 

 laminis latioribus quam altis. Os magnum decies incisum. Spince 

 elongatce, cylindricoe, longiiudinaliter subobsolete striatce, circa 

 1| mm. a basi angulatim dilatatce, ibidem et ad basin granulis 

 circumdatoe ; spatio intermedia laevi, lente, et regulariter attenuato. 



Var. depresses ratio diam. : alt. : : 1 : 1'9. 

 Var, subhemisphcericoe id. : id. ■.: 1 : 1 '5. 



The principal characters of this form are the small and generally 

 equal size of the ambulacral tubercles, and their arrangement: 

 those in the two rows alternating at subequal distances, to- 

 wards the lower portion of the ambulacral areas especially ; near 



