BIOLOGICAL 27 



Among the species which inhabit both areas there are one or two interesting cases. 

 Widely distributed species like Lencothoe spinicarpa, jfassa falcata, and Polycheria 

 antarctica may be ignored ; also Eusirus antarcticiis and Rhachotropis antarctica which 

 are probably more bathypelagic than true bottom dwellers. 



In the same category is Parharpinia sinnata, which like most Phoxocephalids is 

 probably pelagic at night or at certain seasons. Records of Pachychelium and the 

 Metopids are to be used with caution, as these forms are often liable to be misidentified 

 owing to the minuteness of the differential characters. 



Of particular interest, however, is the occurrence of Paramoera gregaria and Talor- 

 chestia sciitigenda at South Georgia as well as in the Tierra del Fuego area. The former 

 is a littoral or shallow- water form, and might conceivably have migrated before Drake 

 Strait became the wide and deep channel it now is. But the latter is a terrestrial form 

 and not improbably dates back to a still earlier period when the Antarctic continent — 

 or at least South Georgia — was connected with Tierra del Fuego (v. Gregory, The 

 Geological History of the Atlantic Ocean, Quart. Journ. Geogr. Soc, lxxxv, Pt. 2, 

 p. cvii sqq. and maps, p. cxviii, 1929). 



There is a strong resemblance between the faunas of the South Shetland Islands and 

 Palmer Archipelago on the one hand, and the Ross Sea area on the other hand, as 

 evidenced by the Acanthonotozomatids, Epimeriids and other forms. 



BIOLOGICAL 



With a view to gaining an insight into the mutual relationships of marine organisms, 

 it may be of interest to collect together lists of those Amphipods which were found by 

 the 'Discovery' in the stomachs of fishes, and those which were found commensal in 

 sponges and Ascidians. 



From stomach of " Perca antarctica ", Blue Fish 1 : Vibilia armata, Cyllopus magellanicus, Phronima 

 sedentaria. 



From stomach of Thynmts pelamys : Phronima sedentaria. 



From stomach of Merluccius : Parathemisto gaudichaudii. 



From stomach of Nancrates ductor : Platyscelus ovoides. 



From stomach of Notothenia : Cheirimedon femoratus, Tryphosa kergueleni, Lepidepecrcum cingulatum, 

 Pontogeneiella brevicornis. 



From stomach of skate (Psammobates) : Phoxocephalopsis zimmeri. 



From stomach of Trigla capensis: Ampelisca palmata, Li/jeborgia epistomata, Melita sitbchelata, 

 Lembos hypacanthus. 



On or in sponges: Lettcotho'e spinicarpa, Seba antarctica, Colomastix castellata, Echiniphimedia 

 hodgsoni, Echiniphimedia echinata, Chosroes incisus, Oradarea tridentata, Polycheria antarctica, 

 Didymochelia spongicola. 



On Cephalodiscus : Podocerus septemcarinatus. 



On the crab Eurypodius : Eurystheus eurypodii. 



In branchial chamber of Ascidians : Orchomenella macronyx, Probohides porceUanus. 



In Medusae : Hoplopleon medusarum, Hyperia galba. 



1 Probably = Seriolella velaini, Sauv., see Regan, Ann. Mag. Nat. Hist. (8), xi, p. 467, 1913. 



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