756 SUMMARY OF CURBENT RESEARCHES RELATING TO 



In the present revision the sections Aporosa and Perforata remain, 

 but shorn of some genera ; the old family Fungidse becomes a section 

 with three families, two of which are transitional between the sections 

 just mentioned. The section Tabulata disappears, some genera being 

 placed in the Aporosa, and the others are relegated to the Hydrozoa. 

 The Tubulosa cease to be Madreporarian. Hence the sections treated 

 are Madreporaria Aporosa, M. Fungida, and M. Perforata. The 

 nature of the hard and soft parts of these forms is considered in 

 relation to classification, and an appeal is made to naturalists to 

 agree to the abolition of many genera, the author having sacrificed 

 many of his own founding. The criticism of 467 genera permits 336 

 to remain, and as a moderate number (36) of sub-genera are allowed 

 to continue, the diminution is altogether about 100. The genera are 

 grouped in alliances, the numbers in families being unequal. Sim- 

 plicity is aimed at, and old artificial divisions dispensed with. There 

 is a great destruction of genera amongst the simple forms of Aporosa, 

 and a most important addition to the Fungida. The genera Sider- 

 astrecB and TJiamnastrce are types of the family Plesiofungidge, as are 

 Microsolenia and Cydolites of the family Plesioporitidfe. The families 

 Fungidse and Lophoseridse add many genera to the great section 

 Fungidae. There is not much alteration in respect of the Madre- 

 poraria Perforata, but the sub-family Eupsamminse are promoted to a 

 family position as the Eupsammidae. 



Prof. Duncan also describes * a new genus of recent Fungida, 

 Family Funginae Ed. and H., allied to the genus Micrahacia, and 

 which he names Diafungia. There is one species, D. granulata. 



Porifera. 



New Gastrseades from the Deep Sea.-f— Prof. E. Hackel has 

 found among the collections of the ' Challenger ' organisms which 

 agree in the following characters ; they live at the bottom of the sea 

 (in rare cases littorally, in the majority at great depths) and have a 

 firm skeleton formed of the substance there found, which they unite 

 into a solid cement by means of a small quantity of organic cementing 

 matter ; some of these skeletons formed quite a museum of Eadiolaria, 

 consisting as they did of the most delicate shells of several hundred 

 species. The skeletons are either external or internal ; the former 

 being due to the secretion of mucus from their outer surface, while 

 in the latter the foreign bodies were taken into the ectodermal cells. 

 In the former the secretion contains no cell-nuclei, in the latter they 

 consist distinctly of protoplasm, in which a few, or in rare cases, 

 a number of nuclei were to be found ; we have then here to do with a 

 more or less modified syncytium. The organisms vary much in 

 form and size, the smallest being from 1-3 mm. in diameter, the 

 largest from 80-120. The organisms that form the cemented skeleton 

 may be either Protozoa or Metazoa ; the former are, in a few cases, 

 colossal Lohosce, allied to Difiugia; in many cases they are true 

 Rhizopoda, and the majority Thalamophora. 



* Join-n. Linn. Soc. Lond. (ZooL), xvii. (1884) pp. 417-9 (1 pi.), 

 t SB. Jenaisch. Gesell. f. Med. u. Naturwiss., 18!S3 (1884) pp. 84-9. 



