RECENT RESEARCHES ON TUE RADIOLABIA. 



189 



by Elirenberg, which he assembled together under the uamc Poly- 

 cystina, and to these living forms were subsequently aggregated. 



Professor Huxley, while on board II. M.S. ' Hattlesnake,' dis- 

 covered certain marine organisms, to which he gave the generic 

 name Thalassicolla ; and his description in 1851* first made known 

 the main points in Kadiolarian anatomy. 



In 1855 John Miiller described f certain star-like organisms 

 to which he gave the name Acanthometra, and subsequently (as 

 before said) united them with other groups as Eadiolaria in a 

 memoir | which is the first great work on the anatomy of both 

 the hard and soft parts of these organisms. 



In 1862 Professor Haeckel published his magnificent and clas- 

 sical work ' Die Eadiolarieu,' containing not only the most com- 

 plete account of the structure of the whole group, but copious 

 references to all preceding writers, as well as a description of a 

 multitude of new genera and species, with an Atlas of thirty-five 

 beautiful folio plates drawn by himself 



Had this illustrious naturalist done no other scientific work, 

 this alone would suffice to procure him enduring fame. 



Since this epoch-making work there have appeared other papers 

 by the same author describing new genera and species, and also 

 papers by Dana, Schneider, Wallich, Stuart, Wagner, Focke, 

 G-reef, Archer, Macdonald, Donitz, Cienkowski, Hertwig and 

 Lesser, and Hertwig, which will be enumerated in the list of the 

 literature of the Eadiolaria at the end of this memoir, and will be 

 incidentally referred to as occasion requires. It will suffice here 

 to make special mention of Cienkowski's researches § on the re- 

 production of Eadiolarians, and of Dr. Eichard Hertwig's admi- 

 rable paper || on the same subject and on the anatomy of certain 

 forms. 



The individual Eadiolarians or zooids vary in size from about 

 ^ J-(5-" to about -gLj"; but they are for the most part invisible to the 

 naked eye, though rarely, as in Myxohrachia (an elongated form), 

 they may attain the length of 14 millims. 



Mostly spheroidal, they may yet be conical, cylindrical, lens- 



* Ann. & Mag. Nat. Hist. ser. 2, vol viii. p. 433. 



t Monatsberichte Berlin, 1855, p. 671. 



X Abhandl. d. konig. Akad. Berlin, 1858, pp. 1-62, pis. i.-ix. 



§ Archiv fiir mikrosk. Anat. vol. vii. p. 371 (1871). 



\ ' Zur Hietologie der Radiolarien,' 1876. 



10* 



