142 Memoirs of the Indian Museum. [Voi,. IV, 



terior margin inside the lateral carina (this is perhaps omitted by error in 

 Pocock-'s figure). 



4. The telson is proportionately broader in 0. latirostris, and the movable tips of 



the submedian spines are shorter. 



5. The terminal movable spine on the outer margin of the uropod fails to reach 



the apex of the ultimate segment. 



In such important characters as the breadth of the eye, the form of the exposed 

 dorsal processes of the ophthalmic somite and the details of the carination of the telson 

 there appears to be the closest resemblance between the two forms. 



In 0. latirostris the lateral margin of the seventh thoracic somite is rounded and is 

 distinctly narrower than that of the sixth, which is truncate. There are ten movable 

 spines on the outer margin of the exopodite of the uropods. 



Borradaile records two specimens of this species, the largest 55 mm. in length, 

 from the Amirante Is., in 25-30 fathoms. 



8. Odontodactylus southwelli, Kemp. 

 Plate IX, figs. 103-106. 

 1911. Odontodactylus southwelli, Kemp, Rec. Ind. Mus., VI, p. 94. 



This species is allied to the two preceding, but may be distinguished from them 

 at a glance by the enormous size of the eyes. Its principal characters are as follows : — 



The rostrum is almost exactly twice as broad as long ; its anterior margin is evenly 

 rounded from side to side and is not depressed in the centre of its distal margin. The 

 eyes (fig. 103) are enormously dilated, the breadth of the cornea being contained only 

 from two to two and a quarter times in the median length of the carapace excluding 

 the rostrum. A greater portion of the ophthalmic somite is exposed than in any of the 

 allied species ; it bears dorsally a pair of strong anteriorly convergent ridges, and in 

 the centre is very conspicuously excavated, the cavity so formed taking the shape of a 

 deep and almost circular pit. The antennal scale is about four-fifths the median length 

 of the carapace. 



The dactylus of the raptorial claw (fig. 104) is moderately dilated at the base and 

 bears seven to nine well-defined teeth on its inner margin in addition to the terminal 

 one. 



The lateral margins of the sixth and seventh thoracic somites are rounded, that 

 of the sixth being a trifle broader and more broadly rounded than that of the seventh 

 (fig. 105). A lateral depression confined by a pair of blunt carinae is visible on the 

 fourth and fifth abdominal somites as in 0. scyllarus and traces of a similar depression 

 may be seen on the two preceding somites. The postero-lateral angles of the fourth 

 and fifth somites are spinous. The arrangement of the carinae on the sixth abdominal 

 somite is similar to that of the two preceding species (fig. 106). The submedian, second 

 intermediate and lateral pairs of carinae terminate in spines ; the first intermediates 

 are connected proximally with the submedians, and the usual proximal denticle inside 

 the laterals is well-marked. 



