468 RECORD OF CURRENT RESEARCHES RELATING TO 



is evident that every part of tlie body-contents, tlie nucleus excepted, 

 is in turn brought in contact with the surrounding water. The com- 

 bined movements present an evidence of vigorous life rarely exhibited 

 among the Ehizopoda, and the transparency of the " test " permits 

 the internal functions of the organism to be as easily followed as the 

 external. 



The specimens observed varied in size between the two extremes 

 of 1*75 and 7*5 mm. in length, and 0*042 and 0*5 mm. in breadth. 



The phenomena connected with the life-history and reproduction 

 of this remarkable Ehizopod have not been fully made out, but the 

 author adds some provisional remarks on the subject, as well as histo- 

 logical details regarding the sarcode and nucleus. He considers it 

 premature to assign it any systematic position until the particulars of 

 its life-history are more fully known. 



The chief food of the animal ajipears to consist of infusoria, which 

 are not, as a rule, conveyed into the body, but digested among the 

 pseudopodia outside the test. 



New Group of Marine Siliceous Ehizopoda— Phaeodaria.* — Pro- 

 fessor Haeckel describes the Phjeodaria, a new group which he 

 proposes to form of large marine Rhizopods, rich in specific forms and 

 remarkable in many respects, which have hitherto been included in 

 the typical Eadiolaria (Sphferidea, Discidea, Cyrtidea, Cricoidea), from 

 which they diifer as widely as do the Acanthometrina. Till lately 

 very few forms were known ; but the explorations of the ' Challenger ' 

 have brought to light a number of new deep-sea species. 



Their size is usually very striking in comj^arison with that of the 

 other Eadiolaria, which they greatly surj^ass in diameter. The greater 

 number are visible to the naked eye, and many are from ^ to 1 mm. 

 or more in diameter. As Murray first showed,! * striking character of 

 all these Ehizopods is the constant presence of large, dark brown 

 pigmented granules, scattered irregularly round the central capsule, 

 and covering the greater part of its outer surface. This extra-cap- 

 sular mass of dark pigment Professor Haeckel calls the Phjeodium 

 (^atos or (^atojSTjs = dark brown, dusky). The Pha3odella or large 

 brown granules of the Phfeodium are not, as Murray supposed,^ 

 true pigment cells, as a true cell - nucleus cannot be observed in 

 them ; and the nature of the peculiar pigment of these pseudo-cells 

 is not precisely known, but the quantity and constancy with which 

 the Pha3odium appears in all Phseodaria, while it is wanting in all 

 the typical Eadiolaria, gives the Phaeodaria a high degree of sys- 

 tematic importance, and it seems to Professor Haeckel at present that 

 the constant presence of the Phfeodium and the peculiarly constructed 

 membrane of the central capsule are the only systematically reliable 

 characters which separate all Pha^odaria from all other Eadiolaria. 

 The characters of the group may be defined as follows : — 

 Single-celled Ehizopods, whose larger cell-body, the central cap- 

 sule (usually round or spheroidal, often, hoAvever, egg-shaped or some- 



* ' SB. Jeu. Gesell. Med. und Naturw.,' 1879, p. 151 ; see Traiisl. ' Nature,' xxi. 

 (1880) p. 449. 



t 'Proc. Roy. Soc.,' xxiv. (1876). J Loc. cit., p. 536. 



