RHIZOPODA. 
Prot. 6 
fath. in the ‘Porcupine ’ expedition of 1869, illustrates in the adult state 
those stages in the evolution of the genus which Carpenter had formerly- 
deduced but not proved. The primordial chamber extends into a closely- 
coiled tube like Gornuspira ; then shows, incipient septation similar to 
Spiroloculina ; then flattens and becomes camerated as a Penoroplis ; 
next, chambers subdivide, converting it into an Orbiculina ; and, finally, 
it assumes the cyclical plan of growth characteristic of Orbitolites. The 
development of this Foraminifer serves as a text for a discourse on 
natural selection. 
Fol, II. Sur le Stilolonche zanclea , et un nouvol ordre do Rhizopodes. 
Mem. Inst. Gen6v. xv. pp. 3-35, pis. i. & ii. [Of. J. R. Micr. Soc. 
(2) iv. p. 73.] 
A detailed account of Stilolonche zanclea , R. Hertwig ; regards it as 
forming a new Order of Rhizopoda , the Taxopoda. 
Foulke, [Miss] S. G. Observations on Actinosphcerium eiclihorni. P. 
Ac. Philad. 1883, pp. 125 & 126. [Cf. Ann. N. H. (5) xii. pp. 206-208, 
and J. R. Micr. Soc. (2) iii. pp. 669-671.] 
Four A ctino splicer ia were seen to fuse ; in an hour, two separated off. 
The remaining mass shortly ejected globules and granules. The former 
emitted a very long filament and others at long intervals, and a miuute 
A ctinosphcerium was formed. This process took from seven to fourteen 
days. 
Gruber, A. Ueber Kerntheilungsvorgange bei einigen Protozoen. 
Z. wiss. Zool. xxxviii. pp. 372-391, pi. xix. [Cf. J. R. Micr. Soc. (2) 
iii. pp. 668 & 669.] 
Observed fission of Actinosphcerium eichhorni in a small specimen; the 
process takes place with great rapidity, without leaving any traces. 
Fission and behaviour of nucleus in Am.cebce. 
Hackel, E. Tiber die Ordnungen der Radiolarien. SB. Jen. Ges., 
translated in Nature, xxix. pp. 274-276 & 296-299. 
This paper gives an account of Hackel’s latest views of the classifica- 
tion of the Radiolaria. In 1881, he distinguished 7 Orders and 2000 new 
species from the ‘Challenger’ collection. This number has since been 
considerably increased, and, as a result, the further knowledge thus ob- 
tained has enabled him to simplify his views, and reduce the number of 
Orders from seven to four — (1) Acantharia , (2) Spumellaria , (3) Nassel- 
laria , (4 ) Phceodaria. For each of these he recognizes an “ancestral 
form,” respectively — (1) Actinelius , (2) Actissa, (3) Cystidium , (4) Phceo- 
. dina. The first, third, and fourth of these may readily be derived from 
the second. The author says, “ Whilst, on the one hand, the simplest 
Spumellaria- form, Actissa, may bo easily accepted as the ancestral form 
of all Radiolaria , Actinosphcerium and Actinophrys show, on the other 
hand, how it may be derived from the simplest Rhizopoda .” The paper 
commences with a brief historical review of the various classificatory 
systems of the group by different authors. His 4 Orders are next pro- 
posed and discussed ; a systematic survey of the 4 Orders, 10 sub-orders, 
and 32 families follows ; and the paper concludes with tables of the 
