68 CRUSTACEA MALACOSTRACA. II. 



42. Leptognathia Sarsii H. J. Hansen. 

 (PL VI, figs. 7 a-7f.) 



1909. Leptognathia Sarsii H. J. Hansen, Vidensk. Medd. Naturh. Forening i Kj0benhavn for 1909, 



p. 229 *). 



1896. longiremis G. O. Sars, Account Crust. Norway, Vol. II, p. 27, PI. XII (Not Tainih 



longiremis Lilljeborg). 



Female. Antennulse nearly three-fourths as long as the carapace. First joint about as long- 

 as the three others combined (fig. 7 a), scarcely two and a half times as long as deep, tapering con- 

 siderably from the base to the end ; second joint slightly longer than the depth of the first and some- 

 what produced above; third joint about half as long as the second; fourth joint distinctly shorter than 

 the upper margin of the second. Antennae with fifth joint a little more than half as long again as 

 the fourth, which is slightly longer than the sixth. 



Chelipeds (figs, ja and 7b) very robust. Carpus only about half as long again as deep, its 

 distal half somewhat expanded downwards, but the convex lower margin of that part without cren- 

 ulation. Chela a little longer than the carpus, twice as long as broad, somewhat triangular in outline; 

 the distal part of the anterior margin slightly convex and furnished with some four to seven sharp 

 or rounded, small saw-teeth; the terminal corner above the insertion of the movable finger is some- 

 what protruding, about rectangular. The outer side of the chela has a row of eight or nine pro- 

 truding teeth situated nearly parallel with and a little removed from the posterior margin, the row 

 beginning with the strongest tooth somewhat near the distal setae of the posterior margin and going 

 upwards on the hand where the teeth are gradually smaller and finally disappear. Half or more than 

 half of the anterior margin of the movable finger is crenulate, with a number of either sharp and 

 triangular or rounded saw-teeth, the finger itself somewhat shorter than the anterior margin of the 

 hand. The subdistal part of the incisive margin of the fixed finger with three sharp saw-teeth, the 

 distal tooth subdivided into two teeth. 



The thoracic legs somewhat slender. Second (fig. jc] and third pairs subequal; posterior ter- 

 minal spine on fourth joint conspicuously shorter than fifth joint; sixth joint almost or fully half as 

 long again as the fifth, slightly or distinctly shorter than the seventh with claw. Three posterior 

 pairs of legs have the seventh joint (fig. 7 d) somewhat shorter than the sixth and furnished with an 

 either distinct or nearly indistinct row of minute, setiform denticles. 



Five anterior abdominal segments with the ventral tubercles high and strong (fig. 7 e). Pleopods 

 with the marginal setae between half as long again and twice as long as the rami. Sixth abdominal 

 segment (figs. 76 and 7f) with the lateral plate on each side produced downwards in a keel which 

 generally projects in a very conspicuous, obliquely triangular, acute process directed downwards and 

 backwards, but in some specimens (from four localities in Greenland) these processes are shorter and 

 obtuse or very short and broadly rounded, but a protrusion is always distinct. - The uropods as long 

 as the sixth and half of the fifth segment combined; the peduncle a little or somewhat less than 

 twice as long as deep, but slightly more than half as long as the first joint of the endopod, which is 



') In a foot-note in his Arctic Crustacea I (Bihang Kgl. Sv. Vet. Akail. Handlingar, B. 26, Afd. IV, No 12, 1901) 

 Ohlin stated that I had proposed the name L. Sarsii for this species. 



