68 SUMMAEY OF CURRENT RESEARCHES RELATING TO 



these are all characterised by a remarkable purple tint, which the author 

 regards as of protective value. It is the complementary colour of the 

 characteristic green of the luminous animals of the abyss, and probably 

 renders the possessors invisible. 



Development of Lebrunia.* — Mr. J. E. Duerden gives an interesting 

 account of the Edwardsia- -tage of the Actiuian Lebrunia, which is in 

 several ways very remarkable. It seems that Lebrunia coralligens retains 

 to a late period certain ancestral characters, which in other forms are 

 either passed over or disappear very early. The early tetrameral sym- 

 metry, followed by a bilateral phase, and that again by the hexamerous 

 adult ; the system of ciliated coelomic spaces connected with a closed 

 archenteron, all imbedded in a mass of undifferentiated tissue ; the for- 

 mation of the oesophagus by the breaking down of the floor of an ecto- 

 dermic invagination in association with an archenteric tube ; and the 

 origin of the adult gastrocoelomic cavity from a primary coelome and 

 disintegration of the tissues, are all unique characteristics. 



Cleavage of Ctenophore Ovum.f — Herr L. Rhumbler has tried to 

 analyse the factors operative in the peculiar cleavage of the Ctenophore 

 egg, and finds one of these in a secondary attraction-centre with radiating 

 rays, which forms the plasmic thickening of the Furchenkopf. 



Porifera. 



Sponges from Celebes.^ — Dr. Johannes Thiele describes a collection 

 of sponges made by the Sarasins. A considerable number of new species 

 are described and figured. 



New Euplectellid.§ — Mr. J. Percy Moore describes Hyalodendron 

 navalium g. et sp. n., from Japan, which would appear to be a type of a 

 new sub-family of Euplectellidse. 



Protozoa. 



Amoebae in Sheep's Lung.|| — M. Louis Blanc notes some of the cases 

 in which amoeboid organisms have been reported as parasites in mammals, 

 e.g. Amoeba coli from the large intestine, various species from the vagina, 

 &c. Hitherto none have been detected in the lung, but Blanc found a 

 colony in the sheep, associated with nodules like those caused by Stron- 

 gylus filaria. The parasite bore a close resemblance to Hyalodiscun Umax 

 or to Amoeba coli, and had doubtless found its way to the lung by some 

 accident in deglutition. 



Coccospheres.lf — Herr C. Ostenfeld has studied some of these much 

 discussed minute organisms from North Atlantic plankton. He has no 

 doubt that Coccosphaera is a living organism, though the dead forms look 

 very inorganic. Adopting Haeckel's title, Calcocyteae, he suggests the 

 following provisional diagnoses : — 



Unicellular pelagic organisms (probably Rhizopods related to the 



* Journ. Linn. Soc. (Zool.), xxvii. (1899) pp. 269-316 (2 pis.), 

 t Arch. Entwickmech., viii. (1899) pp. 187-238 (28 figs.). See Zool. Centralbl., 

 vi. (1899) pp. 8S5-6 (1 fig.). t Zoologica, xxiv. (1899) pp. 1-33 (5 pis.). 



§ Pi-oc. Acad. Philadelphia, 1898 (published 1899) pp. 430-1 (2 pis.). 

 || Ann. Soc. Linn. Lyon, xlv. (1899) pp. 87-9. 

 % Zool. Anzeig., xxii. (1899) pp. 433-9 (2 figs.). Of. this Journal, 1S99, p. 419. 



