NEW SPECIES OF FOSSILS. 37 



on a line crossing the eyes. There appears to be slightly im- 

 pressed glabellar furrow on each side, which commences at about 

 one line from the neck furrow, at about one third the width of 

 the glabella from the side of the same, and runs obliquely for- 

 wards and outwards, reaching the side at about one line behind 

 the eye. In front of this, there appear to be, two small depress- 

 ions in the side of the glabella close to the surface of the cheek 

 and opposite the eye. A line drawn across the head through 

 the eyes would cross the glabella at about one third its length 

 from the front. The eyes are small tubercles, scarcely half a line 

 in diameter, and situated about two lines from the side of the 

 glabella. A small thread like ocular ridge runs from the eye 

 forward, nearly to the front of the glabella, but does not appear 

 to cross the small dorsal furrow which runs round the sides and 

 front. The neck segment forms a vertical elevation along the 

 the posterior margin of the head, half a line in height and curv- 

 ing backwards gradually passes into the posterior prolongations 

 of the head. These as far as they can be seen are nearly ver- 

 tical, but sloping a little inwards and upwards. 



The surface of the whole head is covered with small irregularly 

 polygonal pits separated from each other by sharp edged walls. 

 On the cheeks these pits are on an average about one fourth of a 

 line across, but they vary in size, some of them being much smal- 

 ler than the others. They seem to be in general a little smaller 

 on the glabella than on the cheeks. Where a portion of the 

 crust is broken away, from the front of the head, a cast of the in- 

 ner surface can be observed. It is covered with small round tu- 

 bercles, about three in one line. 



This species differs from Harpes antiquatus, the only species 

 hitherto described from the Lower Silurian Rocks of Canada, in 

 having the glabella more obtusely rounded in front, and in the 

 remarkable characters of the surface which is reticulated, all over 

 the head, by the sharp lines separating the angular puncture, 

 while in H, antiquatus the glabella is smooth or only minutely 

 punctured. 



Dedicated to Mr. William Denton, of Painesville, Ohio, who 

 discovered it. 



Locality and Formation. — Ottawa, Trenton limestone. 



On the Internal Spiral Coils of the Genus Cyrtina. 

 Mr. Davidson, in his monograph on the British Carboniferous 



