OBOLID.E. 515 



Ordovician, appears to be a much larger shell. In Norway and Sweden it occurs m the Cerato- 

 pyge limestone. Compressed and flattened shells from the Paradoxides daindis zone of Manuels 

 Brook, Newfoundland, strongly suggest this species, but no similar forms occur in the calcareous 

 layers interbedded in the shales, altliough L. ferruginea Salter is abundant m both limestone 

 and shale. 



Moberg and Segerberg [1906, pp. 62-63] have described and illustrated five species of small 

 Lingulella-\ik.e shells from the Ceratopijge zone of Sweden. The form illustrated as Lingulella 

 lepis (Salter) [Moberg and Segerberg, 1906, PI. I, fig. 20] is a dorsal valve of that species from the 

 Dictyograptus zone. The form given the name Lingula? corrugata Moberg and Segerberg 

 [1906, PI. I, fig. 21] is from the lower portion of the Dictyograptus zone and appears to be a 

 partly exfoliated dorsal valve of L. lepis. Of the remaining two species, the one named Lingula f 

 ordovicensis Moberg and Segerberg [1906, PI. I, fig. 24] is much like the ventral valve of L. 

 lepis as illustrated on Plate XXXI, figure 4b, of this work, and the other, Lingula? producta 

 Moberg and Segerberg [1906, PI. I, fig. 23], appears to be a similar shell laterally compressed. 

 I have a series of specimens from the Ceratopyge limestone of Norway and Sweden that indicate 

 that the species had a considerable range of variation, in this respect resembling L. ferruginea 

 Salter (PI. XXIX, figs. 1 and 2) ; in fact the variations of the latter species nearly include 

 the forms referred to L. lepis (PI. XXXI, figs. 4, 4a-f). It may be that Moberg and Segerberg's 

 specific names should be retained, but with the information now available I am inclined to 

 consider them all as synonyms of L. lepis. 



The specific name is derived from Xirac, a scale. 



Formation and locality.' — Passage beds from the Upper Cambrian to the Ordovician: (8x) Ceratopyge lime- 

 stone at Slemmestad, about 3 miles (4.8 km.) southwest of Christiania; (323f and 323h [Brogger, 1882, pp. 16-17]) 

 Ceratopyge limestone at Vestfossen, 10 miles (16.1 km.) west-southwest of Christiania; and (323c [Brogger, 1882, p. 44]) 

 Ceratopyge limestone in the Christiania region; all in Norway. 



(320w [Holm, 1898, p. 148]) Ceratopyge limestone at Glote in Herjeadalen, Province of Jemtland; (310 [Moberg 

 and Segerberg, 1906, p. 63]) Ceratopyge limestone (zone 4) at Ottenby, Oeland Island; (310]) Ceratopyge limestone at 

 Borgholm, Oeland Island; (310w [Westergard, 1909, desc. of PI. II]) zone c at Gronhogen, Oeland Island; and (309 

 [Moberg and Segerberg, 1906, p. 63]) Ceratopyge limestone (zone 4) at Fogelsang, 5 miles (8 km.) east of Lund, Province 

 of Malmbhus; all in Sweden. 



Upper Cambrian: (9f) Limestones of the Olenus zone at Noersnaes, west of Christiania; and (323a [Wiman, 1902, 

 p. 66]) Ceratopyge slate in the Christiania region; both in Norway. 



(3211'' and 321m6) Drift bowlders of Ceratopyge sla,te, Nos. 14, 17, and 27 [Wiman, 1902, p. 68], on Biludden, 

 about 20 miles (32.2 km.) east of Gefle, Province of Gefleborg; (309a [Moberg and Segerberg, 1906, p. 62]) Bryograptus 

 slate (zone 2) at Fogelsang, 5 miles (8 km.) east of Lund, Province of Malmohus; (310d) Ceratopyge slate at Borgholm, 

 Oeland Island; and (309b [Moberg and Segerberg, 1906, p. 63]) Dictyograptus slate (zone 1) at Flagabro, Province of 

 Malmohus; all in Sweden. 



(305a [Davidson, 1866, desc. of PI. Ill]) Upper Tremadoc beds at Moel-y-gest, northwest side, Carnarvonshire; 

 (366ci [Davidson, 1866, p. 54]) Upper Tremadoc beds at Garth, opposite Portmadoc, Merionethshire; (305e [Davidson, 

 1866, p. 54]) Upper Tremadoc beds near Tai-hirion, Arenig; (305c) Lower Tremadoc slate, everywhere in the Tremadoc 

 district, Carnarvonshire; (305d)o 6 Upper Lingula flags near Tremadoc, Carnarvonshire; (305f)'J Lower Tremadoc, east 

 of Port Nant-y-Ladron, on the Bala Road from Ffestiniog, Merionethshire; (305g) « Lower Tremadoc at Wern; (3051i)o 

 Lower Tremadoc at Borthwood; (3051)" Lower Tremadoc atTrwyn-y-Iago; and (305j)'^ Lower Tremadoc at Cefn Cyfar- 

 nedd; all in North Wales. 



(307a [Matthew, 1903, p. 240])6 Shales of Division C3c2 of Matthew, on McLeod Brook (=Barachoi3 River), near 

 Boisdale, eastern Cape Breton, Nova Scotia, Canada. 



(301e)6 Beds of Division C3a of Matthew; and (301u) shales of Division C3b of Matthew; both [Matthew, 1903, 

 p. 204] in the St. John Basin, St. John County, New Brunswick, Canada. 



LiNGtJLELLA LINEOLATA (Walcott). 



Plate XL VIII, figures 2, 2a-l. 



Obolus (Lingulella) Uneolatus Walcott, 1898, Proc. U. S. Nat. Mus., vol. 21, pp. 408-409. (Described and discussed 

 essentially as below as a new species.) 



General form ovate, with the ventral valve subacuminate, and the dorsal valve ovate to 

 broad ovate. The range of variation in the outline of the valves is quite strongly marked; this 



1 Davidson, ISBe, p. 54. i The species is somewhat doubtMly identified from this locality. 



