372 Dr. T. Scott on some 



G. S. Brady, from the German South Polar Expedition, 

 1901-1903, but differs in the structure of the antennules, 

 the second maxillipeds, and, to a small extent, in the form 

 of the fifth pair of legs. It appears also to he nearly allied 

 to Tisbe avstrina, Scott, from Scotia Bay, South Orkneys, 

 but the end joint of the fifth pair of legs is proportionally 

 narrower. No males were observed. 



Genus Aspidiscus, Norman, 1868. 

 Aspidiscus australis, sp. n. (PI. XIW figs. 1-5.) 



Female. — The antennules are composed of nine articula- 

 tions ; the first three are tolerably stout and elongated, the 

 fourth is also moderately stout, but is little more than halt' 

 the length of the third ; the remaining joints are narrow and 

 short, except the end one, which is moderately elongated, as 

 shown in the drawing (fig. 1). The formula shows approxi- 

 mately the proportional lengths of the various joints : — 



1 .2.3.4.5.6.7.8.9 

 12 15 13 7 4 2 4 5 11' 



The antennae and mouth-appendages are somewhat like 

 those of A. littoralis, G. O. Sars ; the second maxillipeds are 

 small (fig. 2). In the first pair of thoracic legs the first 

 joint of the inner ramus is tolerably large and expanded 

 interiorly at the proximal end ; the second and third joints 

 are small, and the latter is provided with two short claws 

 fimbriated on the lower margin ; tlie outer ramus is shorter 

 than the inner and composed of three joints, the end one 

 being small (fig. 3). Other natatory legs somewhat similar 

 to those in the species mentioned above. Fifth pair with 

 the end joint tolerably large and lamellif orm • its width is 

 about equal to half the length, and its distal end is truncated 

 and provided with three moderately stout and elongated 

 setse (fig. 4). The caudal rami are short. 



Length '8i mm (about g^ of an inch). 



No males were observed. 



Three specimens of this Aspidiscus occurred in a small 

 tow- net gathering collected in the vicinity of the Falkland 

 Islands in Nov. 1909. 



Fam. Thalestridse. 

 Genus Pseudothalestris, Brady, 1883. 

 Pseudothalestris nana, sp. n. (PI. XV. figs. 1-11.) 

 Female. — Ccphalothorax stout, dorsum boldly arcuate, 



