ACANTHONOTOZOMATIDAE 121 



in this specimen, it is obvious that it should be identified with Stebbing's nodosa, which 

 also came from the Falkland Islands. The mouth-parts and the absence of the serrate 

 tooth on the 2nd joint of antenna 1, as well as the dorsal armature, absolutely prevent 

 the inclusion of the present specimen with typical echinata. 



In discussing these forms in the Terra Nova Report, I took the view that the posterior 

 dorsal tooth on pleon segments 1-3 in Dana's figure (copied in Bate) represented a 

 medio-dorsal carina! tooth, not one of a pair of teeth, and that therefore echinata was 

 merely a more spinose form of nodosa, Dana. The present specimen, however, bears such 

 a strong resemblance to Dana's figure, crude as it is, that one's confidence is con- 

 siderably shaken with regard to the identity of echinata with nodosa. 



Unless Dana's type specimen is still available, the matter can never be satisfactorily 

 settled, and it might be as well to ignore nodosa, Dana, completely, recognizing echinata 

 and the Falkland Islands form for which a new name would then be necessary. This 

 course may not appeal to all authors and therefore it may be best to follow Stebbing and 

 identify the Falkland Islands form with nodosa, Dana, adding Stebbing as anct . emendans. 

 As Chevreux quotes Stebbing (1906) one assumes that his specimen corresponded 

 exactly with Stebbing's description. 



The structure of the mouth-parts would seem to indicate that this form is more 

 correctly placed in the genus Iphimediella. See Schellenberg, 193 1, p. 119, pi. 1, 

 fig. a and text-fig. 64. 



Distribution. Hermite Island; Cape Virgins; Falkland Islands; Magellan Strait. 



Genus Gnathiphimedia, Brnrd. 

 Barnard, 1930, p. 352. 



Gnathiphimedia mandibularis, Brnrd. 

 Barnard, 1930, p. 352, fig. 26. 

 Occurrence: 1. St. 27. South Georgia. 1 juv. 4-5 mm. 



2. St. 123. South Georgia. 1 $ 11-5 mm., 2 ovig. $$ 1 A~ 1 5 mm. 



3. St. 140. South Georgia. 6 cJc? 7-10 mm. 



4. St. 144. South Georgia. 2$$ io-5-i2'5 mm., 1 ovig. $ 11-5 mm. 



5. St. 145. South Georgia. 1 <J 11-5 mm. 



6. St. 148. South Georgia. 1 $ 11-5 mm. 



7. St. 159. South Georgia. 2$$ (1 with embryos) 13 mm. 



8. St. WS 33. South Georgia. 1 <$ 8 mm., 1 $ 10 mm. 



9. St. MS 71. South Georgia. 1 $ with embryos 12 mm. 



Remarks. Though the adults are considerably smaller than the Terra Nova examples, 

 in fact suspiciously like margueritei , I see no differences in them except that side-plates 

 1-3 are more or less narrowed below and bifid, and thus approximate to the form of 

 those of typical margueritei; the mandibles are not so heavily chitinized or so blunt 

 apically as in the large Terra Nova specimens, but distinctly heavier than in the speci- 

 mens here referred to margueritei; the characteristic wide notch between the two sharp 

 points on the head is present in all these specimens. 



Distribution. Oates Land, 329-66 m.; McMurdo Sound, 348-547 m. 



D V !6 



