404 Bulletin American Museum of Natural History. [Vol 



XIX. 



mouth must have been at least 75 mm. behind this. As will 

 be observed from the figures, the rostrum of 5. solomonis tapers 

 toward the distal end more rapidly than that of either of 

 the two other species. 

 Locality, Hajula. 



RHINOBATIDiE. 



Rhinobatus eretes, sp. nov. 

 Plate XXIV, Figure 2. 



The type and only known specimen of this species was col- 

 lected at Hajula. It has the number 4500 (3715). As may 

 be seen from the figure, PL xxiv, Fig. 2, the specimen is quite 

 incomplete, neither the extremity of rostrum nor the tail 

 being present. The species has probably resembled R. temn- 

 rostris Davis in having had a much-prolonged snout, but this 

 is uncertain. There appear, however, to be characters which 

 are sufficient to distinguish the present form from the Sahel 

 Alma species just mentioned. 



In general, the type has about the same size as the type of 

 R. tenuirostris. The distance from the pectoral arch to the 

 mouth is the same in the two ; the distance between the inner 

 borders of the hinder lobes of the pectoral fins is a little greater 

 in R. eretes. The differences noted between the two species 

 are the following: 



The concavity of the sides of the head opposite the gill 

 arches is considerably greater in R. eretes than in R. tenuiros- 

 tris. In the latter the pectoral fin extends forward to a point 

 somewhat in front of the mouth \ inR. eretes it lacks about 2 5 

 mm. of reaching a point opposite the mouth. In the type of 

 R. tenuirostris the pectoral measures, fore and aft, 180 mm,; 

 in R. eretes they measure 103 mm. It is thus seen that the 

 latter species has a much shorter fin in proportion to the size 

 of the animal. 



It is evident that the ventral fins are also relatively smaller 

 than in R. tenuirostris. In the latter the length of this fin 

 along the body is 75 mm.; in R. eretes the hinder extremity 

 of this fin is broken away, but the whole length could not have 

 been more than 60 mm. The anterior border of the ven- 



