28 ARKIV FÖR ZOOLOGI. BAND 10. NIO 8. 



Explanation of Plates. 



Mate I. 



Fig. 1. Mola^ 1,5 mm. in length. Horizontal section through 

 the chorda. Microphoto. X 180. 



Fig. 2. Mola^ 5 mm. in length. Horizontal section through the 

 chorda. Microphoto. X 180. 



Plate IL 



Spheroides teskidineus L., 18 mm. in length. Microphotos. X 125. 

 Fig. 1. Transverse section through the anterior part of a prae- 



caudal vertebra. 

 Fig. 2. Transverse section through the centre of a praecaudal 



vertebra. 



Tryckt den 18 februari 1916. 



Uppsala 1916. Almqvist & Wiksells Boktryckeri-A.-B. 



