BALTIC EEGION 605 



fragments,- and contains the phosphatic fragments and entire shells of 

 Obolus apollinis Eichw. and grains of phosphatic nodules. This is the 

 Obolus conglomerate (Ungulite sandstone) found in many places at the 

 base of the Ordovicic. It ranges in thickness from 0.15 to 0.80 meter 

 and passes upward into a glauconitic sand of about 0.1 meter thickness, 

 which also contains fragments of these shells, and which in turn is suc- 

 ceeded by gray, somewhat glauconitic limestone — the Ceratopyge bed. 

 This is characterized b}~ Lycophoria Icevis Stolle}-, and in it I found a 

 specimen of Eortliis cKristianice. Small fragments of Obolus still occur. 



The Ceratopyge bed passes without break into the Planilimbata lime- 

 stone, and this into the Limbata limestone, these being all of the same 

 kind of calcareous sediment with the characters of a typical calcilutite. 

 The scarcity of organisms in this rock suggests that it may be a commi- 

 nuted algal deposit, though no trace of such is found. The section is 

 terminated by a fault. 



The Ordovicic succession of this region in its entirety is as follows, in 

 descending order : 



Leptwna limestone. 



Hiatus — disconformity. 

 Trinucleus shale. 



(I. Red calcareous Trinucleus shales 15 m. 



1. Remopleurides dorsospinifer Portl. 



2. Proctus brevifrons Aug. 



3. Agnostus trinodus Salt. 



c. Gray limestone with fragments of fossils 5-9 m. 



Trinucleus. 



Orthis. 

 b. Black bituminous Trinucleus shale 6 m. 



1. Trinucleus seticornis His. 



2. Calymene trinucleina Linrs. 



3. Remopleurides radians Barr. 



4. Orthis argentea His. 



5. Leptana quinquecostata McCoy. 



(Numbers 1, 3 are characteristic of Dd 5 of the Bo- 

 hemian succession.) 



a. Masure limestone or Knyckelkalk 9-15 m. 



Gray, very hard, knobby limestone with calc spar veins. 

 No fossils. 

 Chasmops limestone. 



b. Macrourus limestone and shale 9 m. 



Chasmops maximus Schmidt. 

 Illcenus linnarssoni Holm. 

 III. parvulus Holm. 



a. Cystidean limestone 15 m. 



Chasmops oldeni Eichw. 



