I50 NATURE AND AFFINITIES OF THE SPONGES. 



the several protests against the views submitted by Professor Haeckel, 

 reference may be made to the communications contributed by the present 

 author to the 'Annals of Natural History' for March and August 1870. 

 The subject on these occasions was approached more entirely from 

 the Coelenterate point of view, the writer being at that time officially 

 occupied in the study, identification, and arrangement of the series of 

 corals, recent and fossil, contained in the Natural History Department 

 of the British Museum. Arguing from such a standpoint, it was sought 

 to demonstrate that between the alimentary systems of the two groups 

 in question there was nothing whatever in common ; that the single, 

 well-defined gastrovascular aperture in a coral, subservient both for the 

 processes of ingestion and excretion, was in no ways comparable to the 

 multifarious canal-system through which, upon every side of its periphery, 

 the sponge-body received its nutriment, and that the assumption by 

 Professor Haeckel of a distinct ectoderm and endoderm in the structural 

 elements of a sponge was by no means clearly demonstrated. His claim 

 of a distinct personality for each oscular area of a sponge-body was 

 likewise contested, and an adhesion given generally to that Protozoic 

 interpretation of the sponge question, then supported in the text-books of 

 Huxley, Carpenter, and other English authorities, and manifested by the 

 investigations of Lieberkuhn, Bowerbank, and Carter, and especially 

 through the more recent investigations of Professor H. James-Clark 

 already quoted. Evidence of a still more substantial nature, tending in 

 the same direction, and emanating from one of the earliest and first 

 authorities in this country upon sponge organization, has next to be 



noticed. 



In October 187 1, Mr. H. J. Carter contributed to the 'Annals of 

 Natural History ' the announcement of his identification, in all of the 

 numerous marine siliceous and calcareous sponge types recently examined 

 by him, of a structure essentially corresponding with that which he 

 previously described as obtaining in Spongilla, and generally indicated 

 their nonconformity with the Coelenterate plan of organization insisted on 

 by Professor Haeckel. As interpreted by Mr. Carter, the " ampullaceous 

 sacs," or other ciliated systems, represented the o'nly essential portion of 

 the sponge structure, the remaining elements compared with these being 

 entirely subsidiary. One especially weak point in Professor Haeckel's 

 aro-ument was further pointed out in his remarks concerning the sexuality 

 of the sponges. In none out of the hundreds of Calcispongiae examined 

 by him with the microscope, Haeckel says, could he detect a trace of 

 fecundatory male elements or zoospermia, and that therefore the bodies 

 subserving the purposes of reproduction constantly present cannot be 

 desio-nated true sexual eggs or ova, but asexual germ-cells or "spores." 

 These spores, or so-called ova, in all the sponges he investigated. Professor 

 Haeckel, moreover, declared to be perfectly naked and destitute of mem- 

 brane, like the flagellate cells from which they proceed ; furthermore, he 



