226 



bella ; ocular fillet broad and indistinct. Fixed cheek triangular, about 

 as wide behind as the length of the dorsal suture behind the eyelobe. The 

 posterior marginal furrow is faintly marked. The dorsal suture arches 

 outward in front of the eyelobe, and behind it goes direct backward and 

 outward to the posterior margin, and in that part is nearly half as long 

 again as the cord of the eyelobe and anterior part of the suture together. 



The pleurae are long and narrow, and have a sharp, deep furrow, which 

 is nearest the posterior margin ; they are sharply bent, and pointed at 

 -the ends. The ring is pushed up in the middle into a pseudo-tubercle, 

 such as is common on the occipital ring of species of this genus. 



Sculpture. A row of faintly marked tubercle-like swellings are found 

 along the bottom of the anterior marginal furrow. The middle piece of 

 the head-shield in all its parts appears smooth, except for a minute punc- 

 tation. 



Size. Middle piece of the head-shield 25 mm. long. It is 25 mm. wide 

 at the anterior and about 40 at the posterior end. 



Horizon and locality. In gray shale of Assise C. 3 c 2 , at McLeod 

 brook, Boisdale, N.S. 



'Compared This species is near Parabolinella limitis of Brogger. It differs in 



-species. * ^s longer and more quadrate glabella. The fixed cheek also is longer and 

 the eyelobe less prominent. Apparently also it is a larger species. 



From P. rugosa of the same author it is distinguished by its more quad- 

 rate glabella and by a different arrangement of the glabellar furrows. It 

 resembles this species in the possession of a comparatively wide area in 

 front of the glabella. The glabella so wide in front (one-seventh wider 

 than at the posterior lobe), recalls that of Ceratopyge forficula, Sars., of 

 a similar horizon in Sweden.* 



PARABOLINELLA (1) cf. LIMITIS, Brog. 



Parabolinella The middle piece of the head-shield of a young individual which, by its 



18 ' form, agrees with the figures of this species, given by Professor Brogger, f 



was found in these beds. Only one example was met with. The size of 



the shield is 2 x 4 + mm. The interior of the shield shows three pairs 



of furrows, a strong ocular fillet, and a well-marked eyelobe. 



* Die Silureschen Etagen 2 und 3, p. 14, tab. 3, fig. 3. 

 f Ibid p. 102, tab. iii, figs. 2 and 4. 



