930 SUMMARY OF CURRENT RESEARCHES RELATING TO 



production of light in animals is of tbo nature of those which nro cffcctecl 

 under the action of ferments, brings forward some now evidence. Ho 

 has recently dcnnonstrated the normal pre>^cnco in the walls of the si2)hon 

 of Phulas (hicfijJns of micro-organisms {BnriUus pholns) which give a 

 brif^ht light when cultivated in a nutrient fluid jn-epared from the phos- 

 phorescent tissues of the living animal. These tissues contain tho 

 substance which M. Dubois has provisionally called luciferine, and on 

 which the ferment acts. The medium in which it acts must have a 

 suitable chemical composition. 



The author considers that he has hero to do with a case of symbiosis ; 

 another case is afforded by Bacterium pelagm and Pclagia noctilnca. If 

 this bacterium be cultivated in gelatin it rapidly makes funnel-shaped 

 openings filled witli a fluid substance ; in this there are a number of 

 more or less long filaments, filled with very small, perfectly rounded 

 spores. By the side of these filaments there are free spores and some 

 mobile rods which become spore-bearing filaments. In pure gelatin 

 these filaments are not luminous, but if placed in nitrogenous bodies 

 which contain phosphorus, such as nuclein or lecithin, they give rise to 

 a beautiful bluish phosphorescence in the parts which are in contact 

 with air. 



It is possible to collect in these cultivation fluids tho characteristic 

 doubly refractive substance which forms the chalky layer of the luminous 

 tissue of various insects, as well as other animals, and the existence of 

 which has been recognized by the author in the phosi)horcscent sea- 

 water of IMcntone. In chemical characters this body somewhat resembles 

 leucin. In addition to it there are found a number of phosphatic 

 crystals which are almost all formed by the oxidation of the phosphorizcd 

 nitrogenous substances which are found in the cultivation fluid. 



The author thinks that these researches enable us to reconcile the 

 theory of photogenic fermentation with the hypothesis of some authors 

 that there is an oxidation of a phosphorus-containing body. 



Distribution by Birds.* — Prof. O. Zacharias notes that although tho 

 transportation of lower aquatic animals by migratory swimming-birds has 

 long been accepted as affording a possible exj^lanation of the similarity 

 of the fauna in widely separated inland basins, until recently little has 

 been done to find out definitely what animals might be thus distributed. 

 M. Jules de Guerne has lately made a careful examination of the organic 

 contents of particles of slime adhering to the featliers, bills, and feet of 

 wild ducks (Anas hoschaa). The webbed feet were washed with especial 

 care, and a microscojiic examination of the water revealed the presence 

 of little nematods, rotifers (Philodinidx), rhizopods (Trinema enchelys), 

 diatoms, desmids, numerous encysted organisms, isolated Cladocera- 

 cggs, pieces of Polyzoon-statoblasts {PJumatellci), and the shell of an 

 ostracod (Cijthcridca torosa Jones). Spores and cysts were also found 

 in slimcTparticlcs taken from tho feathers. 



Mollusca. 

 a- Cephalopoda- 

 Gigantic Cephalopoda.f — In an anonymous article on gigantic 

 Cephalopoda, in the compilation of which considerable use has been 

 inado of Prof. Vcrrill's well-known researches, it is stated that a blood- 

 • Biol. CeiitralU., vUi. (1888) pp. 368-9. t Naturforsclar, xxi. (1888) pp. 231-3- 



