38 JOHAN KIÆR. M.-N. Kl. 



Strenuella primava Brøg. var. baltica, Wiman from the North Baltic 

 Olenellus sandstone (loose blocks), specially notable for its short cervical 

 ring and its long, narrow glabella. 



Strenuella primaeva var. rotundata nov. var. The type of this species 

 is Linnarsson's large specimens from the gra}' wacke shales at Forsemella; 

 in all probability also includes Moberg's specimens Fig. 2 — 3 from Torne- 

 træsk. It is specially distinguished b}' its more rounded glabella. 



Leaving Scandinavia, we find in the eastern part of N. America (New- 

 foundland) a form that approaches very closely to the above Scandinavian 

 form, viz. Strenuella strenua Billings. Walcott's nasuta in particular 

 appears to öfter many points of resemblance. The glabella, however, is 

 shorter and broader, and the pleura of the segments according to Shimer's 

 description appears to have a dift'erent construction. With the main form. 

 it is one of the typical fossils in the Callavia fauna (e. g. Manuel's Brook 

 Section), which as regards age probably agrees closely with the Scandinaviau 

 Holmia fauna. 



Strenuella Linnarssoni nov. sp. 

 (PI. IV, figs. 5—6, V. figs. 7 ID.) 



1883. Ellipsocephalus Nordenskjöldi Lnrs. p. p. Linnarsson. De undre Paradoxides lagren 

 vid Andrarum. (Sveriges geol. unders. Ser. C. No. 54, page 21, Pi. IV fig. 2). 



The specimen depicted in fig. 2, classified by Linnarssox as Ell. Xordertskjöldi, 

 is probably the form described here. 



1902. Ariottellus primaevtts Brøg., C. Wimax, Studien über d. nordbaltische .Silurgebiet, I 

 (Bull, of the Geol. Inst, of Uppsala, Vol, VI, 1902, P. 44). Wiman observes in a 

 footnote that the original of Lixxarsson's fig. 2, PI. IV, iSee above) appears to be 

 an Arioitellus primaeviis. 



Description. This species also is imperfectly known, only the 

 cranidium (without free cheeks) and isolated segments having being disco- 

 vered. It is found only in the calcareous sandstone and it may therefore 

 be assumed that the specimens have preserved their original form quite well. 



The Cranidium is comparatively well rounded, its lengdi somewhat 

 less that the breadth. (Without the free cheeks). 



The Glabella is slightl}' arched, coinparativel}' broad posteriorly, dimini- 

 shing greatl}'. in breadth anteriorh^ and markedl}' rounded in front. It is 

 provided with 3 distinct pairs of furrows, these being situated at an almost 

 equal distance from each other, and are less marked in older specimens. 

 The posterior pair of furrows are bent backwards strongly, the middle pair 

 less so, and the foremost pair almost vertical to the axis. On the anterior 

 rounded part of the glabella we often see an indistinct furrow, that cuts 

 right across. (PI. I\', fig. 6.) 



