320 bulletin: museum of comparative zoology. 



west of Lake Peipus, reaches the coast south of Hapsal and forms a 

 part of the south end of Dago. In the east it outcrops over an area 

 about thirty miles wide from north to south, but south of Hapsal the 

 belt of its outcrops is only a few miles wide. 



The quarry of the type-locality is in a forest about three miles north- 

 west of the Raikiill residence, and is reached by a road branching off 

 from the main road a little to the west of the entrance to the estate 

 (Plate 3, fig. 2). About ten feet are exposed. The lower eight feet 

 consist of well-bedded, probably dolomitic limestone with the beds 

 varying in thickness from three to eight inches and these are exten- 

 sively quarried for construction purposes. Very few fossils are 

 present. The upper two feet consist of thin-bedded rough limestone 

 in which are many corals, chiefly Fawsites gothlandicus, Haly sites 

 catenularia, and Clathrodiciyon vesiculosum. 



Certain beds of this zone are much more extensively exposed near 

 the village Lippa, situated about three miles south of Raikiill. The 

 quarry covers an acre or two and appears to have been continuously 

 operated for many years, but, only about four feet of strata are ex- 

 posed. The rock is a hard, white, crystalline limestone with which is 

 interstratified a little softer, almost microcrystalline limestone of the 

 same color. The former is dolomitic, and both are in beds from three 

 to six inches thick. At the top are myriads of corals, many of which 

 are silicified. They are not uniformly distributed through the rock, 

 but are aggregated in patches and the species are the same as men- 

 tioned for the Raikiill locality and, in addition, many Heliolitidae are 

 also present. A layer of the softer crystalline limestone is particularly 

 characterized by numerous, fine, large specimens of Leperditia keyser- 

 lingi Schmidt. 



A more extensive exposure of this division is near Weissenstein on 

 the Miintenhof estate, where the beds exposed reach a thickness of 

 twenty feet. The lowest fifteen feet consist of well-bedded bluish 

 and yellowish crystalline dolomitic limestone in which only obscure 

 fossils were seen and these were near the top. The beds are from 

 four to six inches thick, and one about two feet below the top contains 

 flattened mud pebbles with the horizontal diameters reaching an inch 

 and the vertical diameters about a fourth as great. Overlying these 

 strata are from five to six feet of cavernous yellow^ dolomite with 

 gnarled structure and a general absence of bedding. This is probably 

 an old coral reef and it still contains numerous poorly preserved 

 specimens of Favosites and Clathrodictyon. Many of these are 

 merely skeletons and after the exterior has been broken, crumble on 

 being touched. 



