COTTIDyE EOSCORPIUS 53 



Family COTTID^. 



47. Eoscorpius primaevus Jordan and Gilbert, new genus and species. 



(Plate XXX) 



This form was obtained from the diatomaceous rock or Miocene 

 sand shale at Bairdstown. In the imprint the head is crushed, the 

 caudal region behind the anal is wanting and the body interiorly is 

 much confused, being crushed at the shoulder girdle. The fossil (No. 

 XXXIX, from Bairdstown, J. Z. Gilbert) permits the following charac- 

 terization : 



Head (205 mm., approximated) in length to the anal fin 1.6 times; 

 depth at ventral fin about 2.5 in head ; at the anterior dorsal 2.7 ; D. rays 

 roughly counted X 20; P. 12 ( ?) ; V. I, 5 ( ?) ; A. Ill, ; vertebrae 

 19-20 + 6 (?). Body rather elongate; scales comparatively small, 

 with coarse, radiating ridges on the exposed surfaces, crossed by very 

 fine concentric striae, without spinous or pectinated margin shown, but 

 few present and not clearly defined ; mouth large, oblique, terminal ; 

 the mandible apparently extending behind the eye, which is rather large ; 

 teeth small, pointed, equal, sharp, and recurving; opercle below the eye 

 well developed; a well-developed suborbital stay, without spines, its sur- 

 face striate and rising to a blunt point in the center; ventral fin weak, 

 its rays about I, 5, inserted in front of the pectoral, its place perhaps due 

 to distortion, and even its existence questionable ; pectoral practically 

 obliterated and displaced, of perhaps eleven rays ; vertebrae as deep as 

 long, with weak spines and frail ribs, the number to front of anal 

 apparently twenty-two, probably about forty in all. 



The dorsal fin had probably about thirty-three rays ; the anterior 

 part consists of about ten short and rather sharp spines ; the inter- 

 neurals are about as strong as the neural spines ; the soft rays following 

 are weaker, as indicated by the interneurals, the rays themselves being 

 obliterated. The dorsal begins about opposite the fourth vertebra; the 

 two dorsals may have been connected ; the second has strong rays indi- 

 cated by the interneurals, but no subsequent rays are shown, all the 

 posterior region being broken away ; the total number may have been 

 from eighteen to twenty-two. 



The anal fin is indicated by three rather strong and three weaker 

 interhsemals. The last of the three slender spine-like rays is stoutest 

 and longest, perhaps equal in length to the rays which follow. The anal 

 fin lies immediately below the middle of the base of the second dorsal, 

 opposite the 22d, 23d, and 24th vertebras. The interhaemal spines would 

 indicate a fin about equal in height to the dorsal, but the rays themselves 

 are lost. The anal was probably shorter than soft dorsal. The eye was 



