1904.] ASELLOXA- GROUP OF CRUSTACEANS. 321 



rounded tubercle below its middle and a couple of minute tubercles, 

 or denticles above the large tubercle ; the edge is besides furnished 

 with some robust setse, increasing much in length downwards and 

 pectinate along their upper margin ; lower end of palmar edge 

 armed with a strong long spine, the structure of which is shown 

 in fig. 2 e ; seventh joint with its short claw claw-shaped, reaching 

 slightly beyond the palmar edge, along its lower margin with fine 

 setse and a row of small strong spines adorned with a few saw- 

 teeth on their lower margin. — In the female the hand is a little 

 smaller and a little shorter in proportion to the depth than in the 

 male, but it difiers especially in the palmar edge, which is feebly 

 convex and quite without tubercles ; seventh joint and claw as in 

 the male. 



Abdominal shield a little bi-oader than long. Each lateral 

 margin with four or five minute spines placed at rather long- 

 intervals, and terminating in the usual triangular tooth at the 

 conspicuous notch ; behind this notch a minute indentation is 

 observed. Posterior margin has its middle portion produced so 

 that a rather low rounded lobe is formed, and almost each half of 

 the margin is moderately concave. 



Uropoda considerably more than half as long as the abdominal 

 shield ; exopod slightly longer than sympod, but considerably 

 shorter than endopod. 



Distal joint of the endopod of second male pleopoda unusually 

 slender and not widened at or beyond the middle ; a short ter- 

 minal portion only half as broad as the remainder, with the end 

 cut ofi" transversely and without any brush. 



Length of the largest male 5'5 mm., of an ovigerous female 

 6 mm. 



Occurrence. Some specimens were taken by the author at 

 Siracusa, Sicily, in depths from 12 to 25 fathoms; four specimens 

 were secured by the Danish botanist. Dr. Bbrgesen, at Ajaccio, 

 Corsica. 



Remarks. This fine species is easily distinguished by the veiy 

 long process on the basal joint of antennae, by first thoracic legs in 

 both sexes, and by the shape and armature of abdomen. — None of 

 the forms mentioned in Carus's ' Prodromus Faunse Mediterranean '^ 

 can be referred to Stenetrium, and the present species seems to be 

 new, though it is probably widely distributed in the western half 

 of the Mediterranean. 



4. Stenetrium haswellii Bedd, 



1 886. Stenetriimi haswelli Beddard, Proc. Zool. Soc. London^ 

 1886, p. 103. 



1886. Stenetrium haswelli Beddard, Isopoda ii. in 'Challenger' 

 Rep. vol. xvii. p. 9, pi. iv. figs. 1-8. 



The only specimen hitherto known is a male described and 

 figured by Beddard. From his long description most of the 

 characters given below have been selected ; some of my state- 

 ments have been deriA'ed from his figures, and from two sketches- 



Proc. Zool. Soc— 1904, Vol. II. No. XXI. 21 



