174 



ROYAL SOCIETY OF CANADA 



MICRODISCUS, Emmons. 

 MiCRODISCUS PULCHELLUS, Hartt {?) 



Mici^odiscus piilchellus, Hartt (M.SS.) 



Microdiscus punctatus, (Salter) Walcott, U. S. Geol. Surv., Bull. 10, p. 24, pi. ii., 

 figs, la to e. 



Microdiscus punctatus, Yax. pulchelhis,Tva,ns.'Roj, Soc. Can., vol. iii., pt. iv., 

 pi. vil., fig. 12a to c. 



Microdiscus pulcJiellus, Faunas of Paradox. Beds, p. 242, pi. xvii., figs. 8a to/. 



A few heads show the presence of this species or of A. punctatus 

 Salt. The material is too imperfect to determine between the two 

 species, but from the presence of well cut glabellar furrows these 

 examples are supposed to be of Hartt's species. 



CONOCORYPHE, Corda. 

 CoNOCORYPHE PusTULosA, n. sp. (PI. I,, figs. 8rt and b). 



A minute species with highly ornamented surface. The centre piece 

 of the head-shield is elongate semi-circular. Dorsal and marginal furrows 

 deeply impressed. Grlabella broad and elevated, having three pairs of 

 faintly marked furrows, the anterior pair pit-like ; the posterior near 

 the occipital furrow, which is impressed all across. OcciiJital ring pro- 

 jecting behind, pointed. Anterior marginal fold strong, armed at the 

 front with a spine. Fixed cheeks tumid, connected in front of the 

 glabella by a narrow ridge. Posterior marginal furrow strongly marked 

 and fold sharply elevated. 



Movable cheek and other ^jarts of the bod}- unknown. 



/SV;///y^Mre.— The surface, except in the furrows, is covered with pro- 

 minent tubercles, in rows ; the tubercles are largest on the fixed cheeks, 

 which carry three princii)al rows, the foremost arching around within 

 the marginal furrow, the second straight across the length of the cheek, 

 the third arching backward ; one row goes along the summit of the ridge, 

 connecting the two cheeks in front of the glabella ; there is an alternate 

 double row on the anterior marginal fold. On the glabella the tubercles 

 are arranged rudely parallel to the furrows ; a few tubercles show on the 

 posterior marginal fold. 



Size. — Length of the middle piece of the head, exclusive of the 

 spines, 4 mm. ; width, 5^ mm. 



This little species adds another to the peculiar final types of the 

 Conocoryphea ; its armature in front is unique for the genus. In its 

 approximated glabellar furrows and comjiaratively large anterior lobe of 

 the glabella, it approaches Walcott's C. reticulata ; but it is quite distinct 



