156 



Dr. R. II. Traqnai)' — On Drcpanaspts. 



elsewhere. The lower boundary of the oral slit is formed by the 

 lower margin of a broad pentagonal plate (m.), which we may call 

 mental. The anterior or oral margin of this plate, which is also the 

 longest, is, however, not quite straight, as it shows a very obtuse 

 -angle in the middle ; the two lateral margins are shorter and 

 slightly convergent posteriorly ; the postero-laterul margins follow, 

 each at an obtuse angle to its respective lateral one, and they meet 

 each other behind also at an obtuse angle, which fits into the wide 

 anterior notch or excavation of the plate next to be described. 



Fig. 3. — Restored outline of the ventral aspect of Drepannsp\s Gmundeueiisis, 

 Schliiter ; surface ornament omitted, and the tail t\yisted round so as to 

 appear in protile. Letterino: as in Fig. 2, but the mouth in front and the 

 supposed cloacal opening- behind arc represented in black. 



This, the great median ventral plate {m.v.), is of a broadly oval form, 

 having a widely open notch or indentation in front which, as aforesaid, 

 receives the posterior angle of the mental plate. In the specimen 

 of which Fig. 2 is a sketch, the hinder exti'emity of this plate is 

 broken off, but in Fig. 3 I have restored its contour from other 



