186 RECENT RESEARCHES OJT THE RADIOLARIA. 



between Radiolariau yellow cells and the green cells of tlieHelio- 

 zoon Acantliocyrtis, deciding that the question cannot be settled 

 till the genesis of both cells is understood ; but that if they are 

 homologues, then the outer wall oi AcantJiocp^tis cannot be the 

 homologue of a central capsule.) 



Also Sitzungsb. d. niederrheinischen Gresellsch. Jan. 1871. 



And Sitzungsb. d. Gresellschaffc f. Natur. zu Marburg, No. 5, 

 1875. 



Caeruthers, W. British Assoc. Eeports, 1872, p. 126, and 

 Quart. Journ. Microsc. Science, (n. s.) vol. xii. p. 397, 1872. 



(On :rra2'W«tr««,ailadiolarianE.hizopod from the Coal-measures.) 



GrREiirACHER. Zeitschr. f. wissen. Zoologie, vol. xix. p. 289. 



(The author, a propos of Acanthocyrtis viridis, expresses his 

 opinion that the Heliozoa are a less differentiated branch from 

 a root-stem, from which the Sadiolaria are a more differentiated 

 branch, bearing to the latter a relation similar to that borne by 

 the freshwater Hydra to the marine Hydroid polyps.) 



Hertwig, Dr. E. Morphol. Jahrbuch, vol. ii. p. 63, pi. iii. 

 (In this the author puts forward his views as to the formation of 

 nuclei from so-called nucleoli.) 



Hertwig, Dr. R. Zur Histologie der Eadiolarien. Leipzig, 

 1876. 



(A most excellent treatise on the structure and reproduction of 

 Gollozoum inerme, Tlialassicolla nucleata, and Thalassolampe marga- 

 rodes, with considerations on the relations borne by the Eadiolaria 

 to the other Ehizopods, and the bearing of the facts noted on the 

 cell-theory.) 



ZiTTEL, Karl A. Handbuch der Palaontologie, I. Band, 

 p. 117, 1876. 



(The author notices the fossil Eadiolaria of the Mesozoic 

 strata.) 



ZiTTEL, Karl A. Ueber fossile Eadiolarien der ob. Kreide. 

 Zeitschrift d. deutschen geol. (xes. (1876), Band xxviii. Heft 1. 



Flemmikg, Prof. Walther. Archiv f. mikrosk. Anat. vol. 

 xiii. p. 629, pi. xlii., 1877. 



(An elaborate paper, wherein the author takes occasion to 

 criticise and oppose Dr. Hertwig's views as to the nucleus and 

 nucleolus, their multiplication and reproduction.) 



