1S92.] -^^^ [Cope. 



ular rami, and a median gular bone which joins the gulars with a con- 

 cave suture. The gulars are large, and measure three times as long as 

 wide at tlie middle. They are cut off obliquely on the inner side poste- 

 riorly, by the chevron-shaped arrangement of the pectoral scales. Several 

 large external gulars. The posterior extremities of the mandibles are 

 broken so that their proportions cannot be exactly ascertained, but the 

 length preserved is six times the width opposite the anterior gular. The 

 surface of their inferior portions is marked by coarse impressed punctures 

 besides the usual minute ones. The former are not present on any other 

 part of the fish. 



The scales are large ; between the bases of the pectoral and ventral fins 

 can be counted about twenty -one rows, and between the ventral and the 

 first dorsal immediately above, eight rows. The first dorsal fin is above 

 the ventral, and the second dorsal above the anal. There are two large 

 scales on each side which embrace the base of the first ray of the first 

 dorsal and anal ; the other fins are too imperfect at the base for description. 

 The caudal fin is shortly heterocercal, and there are six broad fulcral scales 

 protecting the side of its inferior border. In all the fins the rays are seg- 

 mented. A half dozen rays near the border are coarse, but the remain- 

 ing rays are finer. In all the fins the coarse rays are distally subdivided. 



Measurements. 



MM. 



Total length of specimen (20 mm. intercalated behind head) 950 



Length to anterior border of orbits 45 



Length to posterior border of parietals 143 



Length to posterior border of operculum 230 



Length to anterior base first dorsal fin 620 



Width between orbits 33 



Width of parietals -j- postfrontals anteriorly 38 



Width of parietals and pterolics posteriorly 75 



Length of symphyseal bone 15 



Length of anterior gular 13 



Length of gular 120 



Length of first dorsal fin 110 



Length of caudal from inferior base to superior free apex — 135 



Depth of body at first dorsal 85 



Depth of body at second dorsal 50 



This species is not nearly allied to the species from the Permian of 

 Texas, the 31. nitidus Cope, which is smaller and more robust in form. It 

 has its scales and ganoine, generally, perfectly smooth, and there are but 

 fourteen rows of scales between the pectoral and ventral fins. From the 

 European species with punctate ganoine it differs in the longer gular 

 bones and more elongate head, so far, at least, as concerns the M. Mbbertii 

 and M. laticeps. In M. pygmmus the scales are described as coarsely 

 punctate by A. S. Woodward. Its dimensions are about equal to those 



