DESCRIPTION OF SPECIES 335 



times as long as the third, which is very short ; flagellum of four joints ". This description 

 of the peduncle fits the condition seen in the larger specimen, but in the smaller one the 

 third joint is not much shorter than the fourth; the second is the longest in both 

 specimens. The flagellum consists of six, not four joints. The two distal joints are about 

 half the breadth of those which precede it ; the penuhimate is short and bears a sensory 

 seta at its anterior distal angle, the terminal is long and bears three long deUcate setae 

 at its extremity (cf. a similar arrangement in S. mimita, Beddard). A sensory seta is 

 present at the anterior distal angle of each of the third and fourth joints. 



According to Hale the two terminal joints of the peduncle of the antenna are sub- 

 equal ; actually, however, the terminal one is considerably longer than the fourth, and is, 

 in fact, slightly longer than the third and fourth together. Groups of delicate setae 

 spring from shallow depressions on the anterior margins of the fourth and fifth joints 

 and one or two delicate plumose setae are also present on the dorsal surface of the fifth 

 joint. The flagellum consists of eight, not six joints. The terminal one is narrow and bears 

 a group of long delicate setae at its extremity ; similar setae are present at the anterior 

 distal end of each of the other flagellar joints except the first. 



It is impossible to make out any of the structure of the mouth-parts from the speci- 

 mens. The second pair of thoracic appendages is modified in the usual way: the inner 

 margin of the dilated propodus is armed with a row of three-pronged spines alternating 

 with a row of broad leaf-like structures very similar to, though slightly broader than, the 

 corresponding structures in S. minuta, Beddard, which are figured in the Challenger 

 Report (1884, pi. vii, fig. 7). These are flanked by another row of spines, the distal ends 

 of which appear to be covered with very short closely-set hairs. The dactylus bears a 

 strong short spine near the distal extremity of its inner border. The carpus is crenulate 

 and bears two short stout spines, the distal ends of which are obliquely truncate and 

 covered with short hairs ; a few more delicate spines similar to those which flank the 

 inner margin of the propodus are also present. 



The remaining appendages are all more or less alike, the last pair being somewhat 

 smaller than the rest ; the setae on these appendages are all simple, long and delicate 

 (cf. S. mimita, Beddard). The protopodite of the first three pairs of pleopods is com- 

 paratively long and slender, and, as in the other Australian species, the inner margin is 

 not produced to form a triangular process bearing plumose setae. The suture of the 

 exopod of the fourth pleopod is transverse ; short plumose setae are present on its outer 

 margin, at any rate at the distal end. The endopod is considerably smaller than the 

 exopod and has a rounded extremity. 



The protopodite of the uropod has its inner angle not much produced ; the endopod 

 is longer than the exopod and extends nearly to the tip of the terminal segment. Both 

 lobes are long, with their distal rounded ends sparsely fringed with delicate plumose 

 setae. The colour of the spirit specimen is rather dark brown. 



Distribution. Outside Trinity Opening, Low Isles, Great Barrier Reef, 16° 17' S, 

 146° 2' E, in 200 m. 



The species appears to resemble very closely the two Australian species -S. mimita, 



