82 Aug. F. Foerste 



of the anterior border of the cephalon which lies between the facial 

 sutures, have straightened outlines. The anterior pair of furrows 

 limiting the glabellar lobes is short and rather indistinct. The sec- 

 ond and third pair are distinct but shallow. The nuchal furrow and 

 its extension across the posterior part of the fixed cheeks are still 

 more distinct, but much' less conspicuous than in most species of 

 Calymene. The grooves limiting the glabella are broad and shal- 

 low. The convexity of the glabella above these grooves does not 

 exceed 2 mm., the border of the cephalon anterior to the glabella 

 is not turned up but lies in about the same plane as the lateral mar- 

 gins of the cephalon. The shell appears smooth to the unassisted 

 eye, but under a strong magnifier is minutely dotted with lighter 

 colored spots. The postero-lateral ends of the fixed cheeks and all 

 of the movable cheeks are absent. 



A pygidium found in the same strata and at the same locality 

 (plate III, fig. 21) may belong to this species. There is a strong 

 axial lobe, with about 6 segments, and an undivided posterior por- 

 tion. The lateral lobes are divided into 6 segments, with a faint in- 

 dication of a seventh. The groove limiting the axial lobe curves 

 around its posterior end and separates it from the posterior margin 

 of the pygidium. The lateral margins are deflected sharply down- 

 wards, the width of this deflected margin narrowing posteriorly, 

 and disappearance along the median parts, behind the axial lobe. A 

 ridge, interrupted at the furrows between the pleural segments, oc- 

 curs along the line of deflection. 



This species evidently is closely related to Calyincnc christyi, 

 from the lower part of the Waynesville bed, near Oxford, Ohio. 



Calymene senaria, Conrad. 



(Plate II. fig. 14.) 



In the American Museum of Natural History, in New York 

 City, there is a specimen from the Trenton at Middleville, New 

 York, which is labelled as Calymene calliccpliala. and numbered 

 843-7. The length of the specimen is about 59 mm.; of this, 15 

 mm. belong to the cephalon, 31 mm. to the thorax, and almost 14 

 mm. to the pygidium. The width of the thorax immediately be- 

 hind the head is 30 mm., narrowing gradually to about 21 mm. to- 

 ward the pygidium. The most striking feature of this specimen 

 is the nasute outline of the anterior part of the cephalon. This 



