LOWEi; CAMBlilAX. 



61 



possibly owe its presence to the arms or tentacles of medusae. He found in 

 the collection of the National Museum at Stockholm a block of rock from 

 Lugnas which he thought showed that " Medusites favosus, at least in this case, 

 gave rise to Eophyton." "Besides the ordinary form of Eophyton," lie savs, 

 "there is found another which can be said to be thread-like, and several such 

 threads often run side by side on the surface of the strata for some distance. 

 It is quite possible that this may be due to the tentacles of medusa'. At any 

 rate, 1 noticed at Kristianburg thai when Cyanea capillata descends to the 

 bottom it allows its tentacles, or part of them, to trail on the bottom." Dr. 

 Nathorst also calls attention to the great resemblance existing between Spiro- 

 scolex spiralis and the tentacles of several medusae. His theory of this resem- 

 blance, as here given, is very interesting and is worthy of careful consideration 

 and experimentation with a view to proving or disproving its soundness. 



Sir William Dawson was convinced that Eophyton could not lie a 

 plant, but markings of the nature of Rabdichnites, which he denned as 

 straight or slightly curved marks usually striated or grooved longitudinally, 

 and either single or in pairs. He considered that the marks owed their 

 origin to furrows produced by trailing pointed objects over the mud. 1 



Dr. Haines identified Eophyton from the Trias by'comparing typical 

 specimens from Lugnas with those found in the " Bunter Sandstein." He 

 agreed with Dr. Nathorst's view that Eophyton is a trail, and not a fossil 

 alga. 2 



Dr. Rauff considers that Eophyton may be of purely mechanical 

 origin. 3 He studied a specimen from Lugnas by cutting thin sections and 

 observing the arrangement of the sandstone. His work is very suggestive, 

 and explains many of the so-called trails and algae I have met with in 

 studying the evidences of life in the Lower Paleozoic rocks. 1 do not 

 think, however, that the specimens illustrated by Dr. Linnarsson, or those 

 in this memoir (Pis. XXXII-XXXVIII), are of mechanical origin. 



Count Saporta discusses three suppositions in regard to the nature of 

 Eophyton: 



1. Tracks of animals, viz, trilobites. 



2. Trails of medusa-, etc 



3. Plant remains. 



1 Am. Jour. Sci., 3d series, Vol. V. 1873, \>. 20. 



- Lor. cit., 1875, p. 245. 



; Neues Jahrbueh fur .Mm , Geol. und Pal., 1891, Vol. II, pp. 100-101. 



