246 CEYLON PEARL OYSTEE REPORT. 



and narrower than the 4th, with 3 irregular rows of similar, but more unequal, spines 

 and setae. Dactylus wide, with 4 long and 4 short spines in 2 parallel longitudinal 

 rows on the front side (fig. 9. pp. 3 ). 



Fourth perseopods : 1st joint oblong, widening distally, and almost as long as the 

 3rd and 4th ; a submarginal row of plumose setse near the hind margin, which ends in 

 a blunt right angle, and a few spines and simple setse on the front margin ; '2nd joint 

 about half as long as the 3rd, which is about three-fourths of the 4th, and has 7 long 

 plumose setae on the hind margin: the 4th is nearly twice as long as the 5th, very 

 spinous on the front and with simple setse on the hind margin ; 5th spinous in front 

 and at the end ; dactylus almost straight, slender, minutely and irregularly 

 tuberculated with a denticle near the points (fig. 9. pp. 4 ). 



Fifth perseopods like the 4th, except the 1st joint, which is more than twice as 

 long as wide, narrowing distally and rounded behind, without setse or spines on 

 either margin ; the 3rd joint has no setse on the hind margin except a distal tuft 

 (fig. 9. pp. 5 ). 



First and 2nd uropods : peduncles with a distal spine at the outer and a seta at 

 the inner angle ; rami straight and subequal. 



Third uropods as in U. norwegica, Boeck, as figured by G. O. Sars (' Amph. of 

 Norway,' Plate 47), except that there are fewer spines on the outer margin of the 

 outer ramus. Telson also as in U . norwegica 



A small male and female from the same tube, with well-developed lower antennae, 

 but only 2 '5 millims. long, might, from observation of external characters only, be 

 U. elegans, Sp. Bate. I have long believed that differences of age would account 

 for some of the species that have been established, and for which I would refer to 

 Mr. Stebbing's valuable paper on the genus (' Trans. Zool. Soc. of London,' vol. 13, 

 Part 1, 1891). The species described above may be distinguished by the curious 

 spiny dactylus of the 3rd perseopods (Plate I., fig. 9. pp. 3 ). 



Family: AEGISSIIlE, hoy. 

 First or upper antennse in the males with the fiagellum longer and more slender 

 than in the females. 



Gnathopods subequal and similar. 



Last one or two pairs of perseopods much more powerful than the rest of the limbs. 



Argissa, Boeck, 1870. 

 Argissa hamatipes (Norman). 



Syrrhoe hamatipes, Norman, 'Brit. Assoc. Shetland Dredging Rep.,' 1868. 



Argissa typica, BOECK, 'Crust. Amph. bor. and arct.,' 1870, p. 15. 



Chimjeropsis danica, Meinert. 



Argissa typica, G. < >. Sars, 'Amphipoda of Norway,' p. 1 II. Plate is. 



Argissa hamatipes, Norman, 'Ann. and .May. Nat. Hist.,' 7, vol. 10, p. 480, 1902. 



Kondatchi Paar ; 17th November, 1902 ; one female with ova. 

 Length 2 - 5 millims. 



