MYSIDACEA— TATTERSALL. 283 



joint longer and }iarrower than the ninth, eleventh and twelfth joints very long and 

 narrow, the twelfth joint terminated by two short filaments. 



Inner uropod slightly longer than the outer, with six distantly placed spines on 

 the inner margin, the most distal one near the apex. Outer uropod with about thirteen 

 spines on the outer margin. 



Telson about two and a half times as long as broad, lateral margins armed with 

 six spines, including the terminal spine on the apical lobes, fifth and sixth spines 

 approximated, the remainder more distantly placed. Terminal spine about one-fifth 

 of the length of the telson. Cleft about one-sixth of the entire length of the telson, 

 about eighteen to twenty teeth on each side. 



Length of adult specimens of both sexes, 12 mm. 



Remarks. — The spinifer group of species of the genus Gastrosaccus is sharply marked 

 off from the remaining species of the genus, by having the endopod of the third pleopods 

 of the male normal in form and armature, and multiarticulate. It comprises the 

 following eight species : — G. spinifer (Goes), G. sanctus (van Beneden), G. muticus, 

 Tattersall, G. simulans, Tattersall, G. hojim,aensis, Nakazawa, G. dunckeri, Zimmer, 

 G. kempi, Tattersall, and the present species. 



Of these, G. spinifer, G. muticus and G. simulans have the posterior margin of 

 the carapace provided with a fringe of filaments. 



G. sanctus, G. kojimaensis and G. dunckeri have a pair of forwardly directed lobes 

 on the posterior margin of the carapace. 



G. kempi and G. australis are without lobes or filaments on the posterior margin 

 of the carapace. 



G. australis may be distinguished from G. kempi by the lobe on the dorsal posterior 

 margin of the filth abdominal somite, by the fewer spines on the lateral margin of the 

 telson and the absence of subsidiary spines between the larger spines of the telson, 

 a feature in which G. kempi is unique. 



All the species of this group are shallow-water littoral forms, in contrast with the 

 normani group of species, which are pelagic and off-shore forms. 



Sub-family MYSINAB. 

 Tribe ERYTHROPINI. 



Genus EUCHAETOMERA, G. 0. Sars. 



6. Euchaetomera typica, G. 0. Sars. 



E. tyjnca, G. 0. Sars, 1884, p. 42 ; 1885, p. 211, pi. 37, figs. 1-20 ; Hansen, 1912, p. 199, pi. 2, 

 figs. 5a-e ; Zimmer, 1914, p. 373 ; Brutomysis vogtii, Chun, 1896, p. 179, taf. 15 {nee Lo 

 Bianco, 1901 and 1904 = E. tenuis) ; Euchaetomera limbata, lUig, 1906, p. 293, fig. 10 ; 

 Euchaetomera Sennae, Colosi, 1918, p. 7 ; 1920, p. 239, figs. 4a-4c. 



Occurrence. — North of New Zealand. Station 80, one immature male, 5 mm. ; 

 Station 130, one immature, 4 mm. ; Station 139. one $, damaged, ca. 7 mm. 



2 T 2 



