OP PLANORBIS AT STEINHEIM. 91 



Formation "p," New Pit. 



This consisted of alternate thin layers of clay and limestone, containing remains of PI. 

 oxystomus, PI. crescens, and PI. trocUformis, the last very abundant in the lower part, 

 and very rare in the upper part of the formation. 



New Pit, Section 7, East side. 



The species of the formations in this section did not seem to require figuring. The 

 beds are remarkably distinct in aspect from those of the more regular layers on the south 

 side of the same pit, as shown in section 8. 



Formation "g," TTew Pit, East side. 



This formation was made up of alternate layers of limestone and shell-sand, containing 

 the usual PI. trochiformis and discoideus, but no other forms were present, or represented 

 in my collection. 



Formation "h," New Pit, East side. 



This narrow streak of shell-sand was perhaps one of the most remarkable deposits which 

 it was my good fortune to find. It was an almost solid bed of shells, consisting largely of 

 the transition form, PI. '"uc^dmt^ ■ Quite a number of the PI. discoideus and PL 

 trochiformis were also present in all varieties and some very remarkable forms, produced 

 by distortion of the spiral, arising from wounds. 



Formation "i," New Pit, East side. 



The lower part of this formation presented a very close resemblance to Formation " n," 

 of the East Pit, Section 3. It contained lumps of limestone, in a fine sandy clay, and it 

 is not improbable that these show the mode of formation of the numerous dividing layers 

 of limestone, since they are of all degrees of hardness and exhibit frequently no definite 

 outlines when in place. 



PL parvus was found, but not very abundant. PL crescens was more abundant than 

 the preceding. PL oxystomus was quite rare. PL trochiformis was abundant, but not 

 so frequent as in the upper part. Var. Kraussii was also found, and PL minutus, but not 

 abundantly. 



Formation "k," New Pit, East side. 



This consists of a thin layer of shell-sand between two layers of clay, and was evidently 

 of very limited extent. The clay on either side contained no fossils. 



PL ™^fe*~ = var. revertens, and the turbinate and flat forms were very abundant. 

 PL crescens was also abundant. PL trochiformis and PL oxystomus were the most char- 

 acteristic and numerous of all others. 



Formation "1," New Pit, East side. 



This consisted of shell-sand. The usual list of shells were found, PL trochiformis 

 being perhaps the most abundant form. 



PL minutus. PL crescens. PL tenuis var. Kraussii. 



PL oxystomus. PL trochiformis. 



