434 Chronicles of Science. [July, 



the Monera (a group of simplest forms which he himself discovered) 

 associated with the Flagellata and Diatomaceae as Protista. Haeckel 

 now proposes — with very great propriety, we think — to remove the 

 Sponges from this company, with which they have no close relation 

 at all, their complex aggregated structure finding no parallel in any 

 of the other groups, and the fact that they are "built up of amoeboid 

 and ciliate cells in large measure, being absolutely as true for all 

 animals as for Sponges. Two years since in the Canaries, Haeckel 

 was with his pupil, Miklucho-Maclay, and there the latter paid 

 particular attention to the calcareous Sponges, and both he and 

 Haeckel were much struck with the high degree of organization 

 which these forms presented. Haeckel has since studied the cal- 

 careous Sponges (which are represented by the genus Grantia on 

 our coasts) in the Adriatic ; has found an immense number of new 

 forms, and has watched the development of a great number. He 

 now points out that the central orifice, or " osculum," of such a 

 sponge as Grantia is homologous with the mouth of Ceelenterata ; 

 that the canals of the Sponge too are homologous with the canal- 

 system of Corals, though they open externally by the temporary 

 pores in the former. He describes a small form, Prosy cum, which 

 has not canals opening thus, but only the central orifice, and this 

 he considers very near to the common ancestor of the Sponges and 

 Nematophora (Corals, Hydras, Ctenophora), which he distinguishes 

 as Protascus. Haeckel can distinctly demonstrate an endoderm and 

 ectoderm in many Sponges, whilst in some of the Calcispongiae we 

 have the presence of those radiating septa or " antimera " so cha- 

 racteristic of Corals. The Calcispongiae make the nearest approach 

 to Nematophora by the distinctness of the " persons " which they 

 present, each osculum, or mouth, and canal-system stands alone, 

 like a separate polyp. In other Sponges there is much fusion and 

 merging of persons into a common individuality — in various ways 

 which Haeckel explains — one of these consisting in the possession 

 of a single osculum by several persons. Professor Haeckel's pro- 

 posal has already been attacked in England by Mr. Kent, of the 

 British Museum, who thinks that the osculum of a sponge cannot 

 be the homologue of the mouth of a sea-anemone, because the water 

 runs in at the latter but out at the former — really no reason at all 

 as far as homology is concerned. He also thinks Ceelenterata differ 

 from Sponges in having free-will, which Sponges have not, and 

 declares the Sponges to be the head of the Protozoa. 



Spermatophores in Fresh-icater Annelids. — In the last number 

 of the ' Quarterly Journal of Microscopical Science,' Mr. Piay Lan- 

 kester announces the discovery of these structures in the genera 

 Nais, Tubifex, Limnodrilus, and Clitellis. Peculiar elongate bodies 

 fringed with slowly-moving cilia, and occurring in the seminal 

 receptacles of Clitellis and Limnodrilus, had been described under 



