106 RECORD OF CURRENT RESEARCHES RELATING TO 



ceous was tlius confirmed. Dealing with the subject somewhat more 

 theoretically, Mr. Carter points out that, although when they are 

 cleansed from sea-water, or rather from chloride of sodium, the spi- 

 cules of the calcareous sponge may be preserved indefinitely, this 

 cleansing can hardly have taken place in the medium in which such 

 must have flourished, while in the rich supply around his home he 

 has never found any Calcisponge, although he has often come across 

 a Lithistid which in appearance was very similar to the Faringdon 

 sponge, and only differed in being silicified instead of calcified ; 

 had they been deposited in the coral rag instead of in the ujgper 

 greensand they too might, he thinks, have been calcareous ; and he 

 comes to the conclusion that " most, if not all, of Professor Zittel'a 

 fossil Calcispongije may, after further examination, have to bo 

 transferred to other orders." 



Protozoa. 



Multinucleated Animal and Vegetable Protorganisms.* — M. E. 

 Maupas recalls, as instances of the plurality of nuclei in a cell, those 

 in Euchelys gigas, Opalina, Actinosphcerhmi, the Foraminifera, &c., a fact 

 which has much embarrassed writers on cellular morjphology, some of 

 whom, attaching great importance to the nuclei, see in their multi- 

 plicity the indication of a multicellular condition ; others, on the 

 contrary, consider them as simple fragments in no way affecting the 

 individuality and unity of the cell. 



The author has reconsidered the question, and has examined Infu- 

 soria, a fungus, Empusa muscarina, and four algae (three Cladophora 

 and one Vaucheria, one of the former being marine). 



The Empusa was taken during its vegetative period, when it was 

 seen to be marked with numerous bright spots very close together, 

 which some authors describe as vacuoles, but which are really small 

 nuclei of about 4 /x in diameter. To demonstrate this, the Empusa 

 can be treated in the manner already described f for the zoospores 

 of algee, that is, by alcohol, j)icrocarmine, and crystallized acetic acid. 

 The nuclei are very numerous, and scarcely sej)arated from one 

 another by more than two or three times their diameter. 



The nuclei of Vaucheria and Cladophora, disguised by chlorophyll, 

 are more difficult to show. They should be soaked in alcohol for 

 twenty-four hours to decolour them, and then ti*eated with picro- 

 carmine and acetic acid. The tubes of the Vaucheria and the cells 

 of the Cladophora will then be seen to have a great number of rose- 

 coloured nuclei similar to those of the Empusa. In the marine Clado- 

 phora there were from 150 to 200. They are quite distinct from the 

 amylaceous corpuscles, which do not take the rose colour. 



The same was observed in four Infusoria of the genera Enchelyo- 

 don, Euchelys, TJrolepsus, and Oxytricha. 



Another organism observed was a fine fresh- water rhizopod, which 

 was unprovided even with a peripheral membrane, and was composed 

 of irregular sarcodic masses of variable dimensions, united by fine 



* ' Comptes Rendus,' Ixxxis. (1879) p. 250 ; see also mfra, p. 111. 

 t Ibid., Ixxxviii, (1879) p. 1274 ; see this Journal, ii. (1879) p. 609. 



