MACRUEA. 79 



The rostrum is straight and slightly arched, semi-transparent except on the ventral 

 side, which is strengthened by a thick ridge. There are nine dorsal teeth, the 

 posterior of which is a little remote from the others and is situated on the carapace. 

 There are two minute teeth at the tip of the rostrum on the ventral side. The 

 rostrum reaches almost to the end of the 2nd segment of the antennular peduncle. 

 The antennular peduncle has the 1st joint broad and flattened and equal to the sum 

 of the 2nd and 3rd. There are two fiagella, the outer of which is thicker and shows 

 signs of bifurcation at its distal extremity. The flagella are slightly longer than the 

 peduncle. The antennal peduncle is half as long as the 1st joint of the antennular 

 peduncle. The flagellum is about as long as the body. The antennal scale is slightly 

 longer than the antennular peduncle. The eye stalks are long and the eyes project 

 laterally. The carapace 1 tears on its anterior margin a well-developed spine below 

 the eye and also a smaller spine ventral to this. There is also a large hepatic spine. 

 Running along the carapace are two slight grooves. The dorsal groove starts behind 

 the antennal spine and extends half the length of the carapace. The ventral groove 

 starts at the anterior ventral border and traverses the entire length of the carapace in a 

 sinuous manner. The first two pairs of legs are chelate, the second pair being longer 

 and stouter than the first. The last three pairs are long and slender and have the 

 dactylos biunguiculate. The abdomen is more than three-fourths the length of the 

 body and is suddenly bent at right angles at the 3rd segment, the dorsal part of 

 which is much swollen. The dorsal side of the last three abdominal segments forms 

 a straight line. The (3th segment is long, being about one and a half times as long 

 as the 5th, and equal in length to the telson. The telson is slightly shorter than the 

 uropods and ends in two spines. 



General distribution : Atlantic coasts of North America, Ceylon. 



Family : LATREUTID^. 

 Nauticaris, Sp. Bate, 1888. 

 Nauticaris grandirostris, n. sp. Plate I., fig. 6. 



Locality : Galle (Station XXXV.), 2 males. 



The carapace has a prominent antennal spine and a spine at the antero-lateral 

 border, as well as a spine on the anterior border half-way between these two spines. 

 The median dorsal surface of the carapace is occupied by well-marked teeth, which 

 are continued on to the rostrum. There is a well-developed rostrum, two-thirds as long 

 as the carapace. The rostrum is deep and is turned upwards at the tip. There are 

 six teeth occupying the whole of the mid-dorsal line of the carapace and the posterior 

 half of the rostrum. Of these teeth the posterior one is very small and not easily 

 made out. The others are well developed, the anterior tooth being slightly smaller 

 than the rest. Only the first two of these teeth are situated on the rostrum. The 

 anterior half of the rostrum bears no dorsal teeth. The extremity is marked by 

 three small teeth. On the ventral side there are six teeth, the posterior four being 



