I 12 



The capital urn is elongate, about twice as lono; as broad. Bat. It is not covered by 

 membrane and the lines of growth of the different valves are not very distinct. Though the 

 carina is not strongly bowed, the carinal side of the capitulum is more strongly convex than 

 the rostral or occludent side. There is no rostrum, hence the total number of the valves is 

 thirteen. The scutum and the upper latus are of considerable size and very peculiar shape. 



The scutum is large; in consequence of the shortness of the basal margin the shape 

 of the scutum is almost triangular. The occludent margin is straight, only feebly convex in the 

 upper part. The tergal margin is rather long; it forms a small slightly recurved apex with the 

 occludent maro-in. The lateral margin has a depressed angle slightly above the middle of its length. 



The tero-um is medium-sized. Its occludent margin is convex; its carinal margin slightly 

 convex in the lower and hollowed out in the upper part ; its scutal margin is feebly hollowed 

 out about the middle. The apex of the tergum is distinctly recurved, but blunt, not pointed. 



The carina is rather long, reaching to ''/V''^ of the length of the carinal margin of the 

 tero-um. It is not strongly bowed and its sides are only well-developed in the upper part. The roof 

 increases in width from the apex downwards; it is not bordered by ridges, but laterally convex. 



The upper latus is very large and of an irregular, elongate hexagonal shape. The 

 umbo is almost in the middle of the scutal margin, where a slight convexity fits into the 

 depressed angle of the lateral margin of the scutum. The length of the different margins can 

 be seen in the figure. 



The rostral latus is very small, its shape is distinctly pentagonal. Its rostral margin 

 is considerablv longer than the lateral margin, which separates it from the infra-median latus. 



The infra- median latus has the umbo at the apex. It is a narrow and relatively 

 short valve. 



The carinal latus is irregularly pentagonal. Its carinal margin is divided into two 

 nearly equal parts at an angle with one another. The upper part is hollowed out for the 

 reception of the basal part of the carina. The upper margin has a slight e.xcrescence about its 

 middle point. The lateral margin is the shortest of all. 



The peduncle is short, cylindrical, slightly broader at the upper extremity. Its surface 

 bears rather broad and narrow scales placed in not quite regular rows: one at the carinal and 

 one at the rostral side alternating with one placed in the middle of the left and one in the 

 middle of the right .side. 



Size. The total length of the specimen figured is 7,5 mm., that of the capitulum 6,6 mm. 



The study of the structure of the animal contained within the capitulum has yielded 

 the following results : 



Mouth slightly bullate, with the part directed forward rounded. La brum with a row 

 of small but distinct teeth, those in the middle of the row slightly larger and distinctly pointed. 

 Palpi slender, with a few short hairs along the outer margin and a couple slightly longer 

 near and at the tip. 



Mandibles with three equally distant teeth and the distance between the third teeth 

 and the pectinated inferior angle very short. 



Maxillae with a distinct notch about the middle of the edge : with four spines, two of 



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