Chilton. — Some New Zealand Amphipoda. 227 



Jassa frequens (Chilton). (Fig. 4, A to D.) 



Podocerus frequens Chilton, 1883, p. 85, pi. 3, fig. 2. P. latipes 

 Chilton, 1884, p. 258, pi. 19, fig. 2 a-d. Jassa frequens Stebbing, 

 1906, p. 656. J 



This species was described under the name Podocerus frequens in 1883 

 from a number of small specimens obtained in Lyttelton Harbour, and 

 although male and female were described it is probable that none of them 

 were quite fully developed. In the following year other specimens similar 

 in general character but differing somewhat in the second gnathopods, and 

 particularly in the greatly broadened character of the fourth peraeopod, 

 were obtained from the same locality and were named Podocerus latipes, 

 it being suggested, however, that they might prove to be only a variety 

 of P. frequens. In 1906 Stebbing combined these two species under the 

 name Jassa frequens, regarding the form described as P. latipes as the male. 



The species is fairly common in Lyttelton Harbour at the roots of 

 Macrocystis and other seaweeds above low-water level, and I have numerous 

 specimens and can therefore add something to the descriptions previously 

 given. I am not certain about the generic position of this species, but on 

 the whole it seems to come within the characters of Jassa, the name now 

 adopted for the genus Podocerus, except that I cannot find upturned teeth 

 on the outer ramus of the third uropod, both rami being apparently free 

 from these teeth. The broadened character of the fourth peraeopod proves, 

 however, not to be confined to the male, but to be present also, sometimes 

 apparently even to a greater degree, in the female. The differences between 

 the two sexes in the second gnathopod are not greatly marked, but in the 

 female the palm of the propod is slightly concave and the basal part of the 

 propod is not produced into a distinct process as it is in the male ; in the 

 male this process is stout and truncate at the end, but the whole gnathopod 

 is not greatly larger than in the female. One or two specimens, however, 

 which, from the shape of the second gnathopod, woidd be considered males, 

 bear brood-plates on some of the peraeopoda. 



Ischyrocerus anguipes Kroyer. 



Podocerus cylindricus Kirk, 1879, p. 402. Wyvillea longimana 



Haswell, 1879, p. 337, pi. 22, fig. 7 ; Stebbing, 1906, p. 648. 



Podocerus longimanus Chilton, 1884, p. 255, pi. 17, fig. 2 a-e. 



Ischyrocerus anguipes Sars, 1894, p. 588, pi. 209 ; Stebbing, 1906, 



p. 658. 

 This species was first recorded from New Zealand by T. W. Kirk in 

 1879 from specimens collected at Worser Bay, Wellington, which were 

 by him identified as Podocerus cylindricus Say, the identification, however, 

 being subsequently questioned by Miers (1880, p. 125). In the same year 

 Haswell had described Wyvillea longimana from Port Jackson, establishing 

 for it the new genus Wyvillea. In 1884 I identified specimens taken at 

 Lyttelton as being the same as Haswell's Wyvillea longimana, and pointed 

 out that his generic description had apparently been based on a misinterpre- 

 tation of the terminal uropods, and that the animal in question was the 

 same as the specimens referred by Kirk to Podocerus cylindricus, which 

 I had been able to examine. Owing, however, to Miers's doubt as to the 

 possibility of an Arctic species being found also in New Zealand, I adopted 

 Haswell's specific name, and therefore named the species Podocerus longi- 

 manus. In 1888 Stebbing in his notice of Haswell's paper says, ' The 



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