368 Transactions. 



rows of setae on both margins, palm oblique, defined by a small tooth., 

 irregularly denticulate, the teeth varying in number and being acute or 

 rounded at end ; right and left second gnathopods often slightly unequal 

 in size, those of the male apparently larger and with more distinctly toothed 

 palm than in the female. Third uropods much longer than the first and 

 second, rami equal, broadly lanceolate. Telson cleft to base, lobes bluntly 

 conical, produced into an acute tooth on each side the terminal notch, 

 which bears 2 or 3 spinules. 



Colour. — Usually light yellowish - brown ; " dirty green " (G. M. 

 Thomson). 



Localities. — Moeraki (Dunedin Museum collection) ; Stewart Island 

 (H. B. Kirk) ; Paterson Inlet, Stewart Island (Gr. M. Thomson — recorded 

 as Maera quadrimana Dana) ; Chatham Islands (H. B. Kirk) ; ofi Cape 

 Maria van Diemen, dredged in 50 fathoms (C. Chilton). 



Distribution. — Australia, Kermadec Islands, New Zealand, Chatham 

 Islands. 



The species was originally described from Port Jackson by Haswell, 

 and afterwards recorded under the name Megamoera thomsoni by Miers 

 from various localities in the north of Australia. These two species were 

 united by Haswell (1885, p. 105). I have a specimen from St. Vincent 

 Gulf, South Australia, sent to me by Mr. S. W. Fulton, and in 1911 I 

 recorded it from Kermadec Islands, the specimens having been collected 

 by Mr. W. R. B. Oliver. 



In 1912 I examined a few specimens from Cape Colony collected by 

 the " Scotia " Expedition, and v/ith some hesitation referred them to Maera 

 mastersii, mentioning the points in which they differed from the description 

 given by Stebbing in " Das Tierreich Amphipoda." Mr. Barnard has since 

 kindly sent me further specimens of the same species from Cape Town, 

 and has pointed out that they differ in some specific characters from 

 M. mastersii. I find that this is so, and that they belong to Maera hruzelii 

 Stebbing, a species which I had overlooked, as it was accidentally omitted 

 trom " Das Tierreich Amphipoda." Mr. Barnard considers the Cape Town 

 specimens slightly different from the description of Maera hruzelii, and looks 

 upon them as a separate variety or a closely allied species, and places them 

 in the genus Elasmopus, to which, as I pointed out in 1912, they show con- 

 siderable resemblance. 



Stebbing (1910b, p. 457) gives four points of difference between M. 

 hruzelii and M. mastersii. Two of these hold for my specimens — viz., the 

 accessory appendage is only 4-jointed in M. mastersii but about 8-jointed 

 in M. hruzelii, and the third uropoda reach considerably beyond the others 

 in M. mastersii but only a little beyond them in M. hruzelii. The other 

 two distinctions do not hold ; thus the first side plate is produced forward 

 in M. mastersii about as much as in M. hruzelii, and the palm of the first 

 gnathopod is not quadridentate but smooth. The teeth on the palm of the 

 second gnathopod are sometimes 4 in number. 



Maera mastersii was first recorded from New Zealand by Mr. G. M. 

 Thomson, under the name M. quadrimana Dana, in 1882. Mr. Thomson 

 obtained several specimens with the dredge in Paterson Inlet, Stewart 

 Island, and another from between tide-marks in the same locality. He 

 pointed out that the specimens differed in certain respects from Dana's 

 species, and that they differed among themselves in the structure of the 

 second gnathopods. I find that Mr. Thomson's specimens belong to two 



