350 MESSES. HANCOCK AND HOWSE 



had an impression of the whole fish, marked out by the shagreen, 

 similar to the figure given by Miinster of his Dictea striata. 



The cutting or anterior margins of the teeth are downwards, 

 for the most part buried in the matrix. Many of the roots and, 

 to a great extent, the crushing-disks, having been removed, as 

 before stated, the specimen is as it were hollowed out, and pre- 

 sents an oval disk-like aspect, an inch and three-quarters long, 

 and an inch and a quarter wide. The broken anterior portions 

 of the teeth line this cavity in almost perfect order as if observed 

 from the interior of the mouth, their external or anterior extre- 

 mities being turned from the observer. The group thus seen is 

 divided into two portions, an anterior and posterior. The teeth 

 of the former or upper jaw have their faces or anterior scoop-like 

 cutting-margins and crushing-disks, or as much of them as is left, 

 turned downwards, and are closely packed together in five hori- 

 zontal rows of seven teeth each. The central teeth of the five 

 rows rest one upon the other in the median antero-posterior line 

 diminishing in size forwards and upwards as the specimen is seen. 

 These five central teeth are flanked on either side by three others, 

 which likewise diminish in size in front. These teeth, of which 

 there are in all thirty -five, as already stated, belong to the upper 

 jaw. A similar cluster of teeth belongs to the under jaw, and com- 

 poses the posterior half of the general batch. These are an-anged 

 in the same fashion as those of the upper jaw; but instead of 

 having the anterior scoop-like cutting-margins turned downwards, 

 they are placed in the opposite direction, looking upwards. The 

 anterior margins of the two sets of teeth meet in the transverse 

 middle line, and are pressed close together, so that the entire 

 batch is continuous, there being no hiatus anywhere, the mouth 

 in fact being closed, and the teeth of the two jaws pressed toge- 

 ther. In the under jaw there are likewise five horizontal rows 

 of seven teeth each, though, on account of the injury the speci- 

 men has sustained, the exact number is not so easily determined 

 as it is in the other jaw. 



This specimen has apparently been as complete as that figured 

 by Miinster (Beitr. Heft. v. Taf. 15, figs. 10, 11) under the 

 name of J. Dictea, and is indeed a very good counterpart of the 



