EXCURSION VI. 



127 



fruit of Lepidodendron, and are named Lepidostrobus. There 

 are two other species in the ash beds, L. lotus and L. 

 Wuenschianus. One of Mr. Binney's figures, L. ambiguus, 

 exhibiting the internal structure of the cone, with portion of 

 the stalk attached, is reproduced with permission in our 

 woodcut (fig. 24). 



Fig. 24. 



In the spring of the present year there was found in these 

 beds a palatal tooth of the Ctenodus cristatus, a species of that 

 typical genus of fossil fishes which gives its 

 name to one of the four great divisions of 

 Agassiz, from the structure of the scales re- 

 sembling the teeth of a comb in their marginal 

 divisions. The structure of the scale and 

 tooth is represented on the annexed sketches (figs. 25, 26). 



Westwards of these beds, and of course overlying them 



Fig. 26. 



there succeed sandstones and shales, thin courses of fel- 

 stone or porcellanite occurring in the red shales, and 

 beds of limestone with Producti, species of Echinodermata 



