PLATE XXVIII. 



Medusina princeps (p. 54). 



Fig. 1. Copy of Linnarsson's second figure of Medusina racliata, which Nathorst identified as the 

 species described by Torell. 



MEDUSINA RADIATA (p. 56). 



Fig. 2. Copy of Linnarsson's original figure. Dr. Nathorst considers this to be a cast of the radial 

 canals of a craspedote medusa belonging to the family JEquoridae. 



Medusina costata (p. 49). 



Fig. 3. Side view of a quadripartite specimen showing the radiating ridges and casts of the 



genital hollows (g, g). (Collection United States National Museum.) 

 Fig. 3a. Summit view of fig. 3, showing 4 lobes expanding to hollows in the roof of the gastric 



cavity; also the casts of the genital hollows (g, g). (Collection United States National 



Museum.) 

 Fig. 3b. View of the lower side of fig. 3, showing cast of the 4 radiating ridges and the genital 



hollows (</, g). (Collection United States National Museum.) 

 Fig. 4. View of the under side of a quadripartite specimen. (Collection United States National 



Museum. ) 



Dactyloidites asteroides (p. 41). 



Fig. 5. A specimen flattened in the slate. The exumbrella lobes appear to have been pressed out 

 over the subumbrella lobes, the latter appearing as the dark portions of the fossil. 



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