BIHANG TILL K. SV. VET.-.VKAD. HANDL. BAND. 3. N:0 12. 15 



Gemis Lingula, or Lingulella. 



Pl. III, figs. 24—30. 



Of Linrfula or LinguleUa various forms occur in tlie Para- 

 doxides beds of Sweden, but the materials obtained are very 

 scanty and insufficient, so that it is hardly possible to limit and 

 characterize the species in a satisfactory manner. 



From the other Swedish forms diifers considerably, especially 

 throiigh its comparatively large dimensions, one species, figs. 29 

 and 30, which occurs in the strata with Paradoxides Kjerulli at 

 -^^.ndrarum in Scania. The specimens are, however, too defective 

 to allow a satisfactory determination of the specific characters. 

 Fig. 29, of an external cast, seems to be nearly complete, and 

 to give a tolerably exact idea of the general shape; fig. 30 shows 

 a more mutilated internal cast. The shell is A^ery slightly con- 

 vex. The ontline is ovate or somewhat pentagonal. The surface 

 is not preserved in any specimen, nor are the external casts di- 

 stinct enough to give information of its ornamentation. The. 

 species was first found by Dr. Xathobst, and it may therefore 

 be named Liiupdella ( ?) Nathorsti. The specimens figured measnre : 

 Length 9 mm. Breadth 7,. 5 mm. 

 )) 12 » » 9 » 



In the strata with Paradoxides Forchhammeri there occiir 

 other forms of Lingula or Lingulella, figs. 2-1: — 2^, which are all 

 more convex and of a smaller size, varying from o to 6 m.m. in 

 length. Their shape is somewhat diflferent, but as the materials 

 are very scanty, I do not feel certain, whether they belong to 

 one or more species, and therefore I will not, at present, afiäx 

 to them any specific denominations. Some specimens (figs. 24, 

 2h) are ovate, with the sides curved and gradually merging into 

 the obtusely pointed beak. In others (fig. 28) the beak is more 

 acutely pointed, with nearly straight slopes. Finally, the shell 

 is in some specimens (fig. 26) somewhat pentagonal, though not 

 with quite straight sides. The shell surface is in none so well 

 preserved that its ornamentation can be made out. The interiör 

 is almost unknown. li\ one specimen a low, flattened, or somewhat 

 concave, mesial ridge is seen to extend, slightly widening, froin 

 the beak to about the middle of the shell. In the same specimen 

 small punctiform pits, resembling those occurring in the interiör 

 of Lingulella Davisi, are seen. — The forms here referred to 

 occur in the strata with Paradoxides Forchhammeri at Kinne- 



