488 
PHOTOZOA. 
CollQzmtm inerme. ■ On jts non-sexual reproduction^ cf. A. Stuart, Nachr. 
Ges. Gotting. 1870, pp. 100 & 101. 
A. Schneider publishes observations on Acanthocystis virulis, Actinophrys 
^ichhomi) and Diffluyia. The genera Acanthocydis and Aulacantha appear 
to bo very closely allied, if not identical. DiJjHiiyia proteifonnis, oblonya, and 
acuminata^ Ehrenb., and the other large species, belong to the lladiohria \ 
and D. enchely^f Schn., nec Ehrenb., should either be referred, to Arcella or 
to a new genus. Zur Keimtniss der Radiolarien,” Z. wiss. Zool. xxi. pp. 605- 
512, Avoodcuts ; cf. Z. ges. Naturw. (2) iv. pp. 338-310. 
R. Gbeefp, SB. Ver. Rheinl. xxviii. pp. 4-8, refers Actinophrys sol, A. eich- 
Jiorni, and Acanthocystis viridis to the Radiolaria, fam. Acanthometridce. A. 
t^ichhorni consists of 4 layers; — (1) the external layer of pseudopodia (which, 
however, are not true pseudopodia, as they originate in the interior of the 
body) j (2) close alveolar layer ; (3) homogeneous vesicular zone j (4) nu- 
cleated central substance. A. eichhorni reproduces itself non-sexually by 
fission, dividing into two halves, sometimes of nearly equal size, and some- 
times differing in size. An individual disturbed in the act of division will 
often contract itself again into one animal, a process which has been mistaken 
for conjugation. It is probable that the internal substance sometimes deve- 
lops embryos in the form of amcebm, as Greett' has seen amoebm which subse- 
quently developed a flagellum issue from the body of a large dead A. eich^ 
horni Actinophrys sol also reproduces by fission j and the two halves often 
jemain connected for a time, but never reunite again into one. This, again, 
is not true conjugation. 
Actinqsphcerium eichhorni. On a very remarkable form somewhat resem- 
bling this species, cf. W. Archer, Q. J. Micr. Sci. xi. pp. 101-104. 
J. D. Macdonald, Ann. N. H. (4) viii. pp. 224-226, has observed 6 genera 
of Diatomacece and 6 of Polycystina in a bottle of deep-sea soundings obtained 
by Staft-Capt. Oalver, of H.M.S. ‘ Porcupine,’ in lat. 47° 35' N., long. 12° 
15' W. ; depth 2435 fathoms, or 3 statute miles. lie has never seen any 
evidence of the existence of pseudopodia in genuine Foraminifera) and perfect 
fixity has been the rule, either by a broad base or a pedicle. lie remarks on 
the sarcode of the various Ibnns, the mode of deposition of their shells, and 
their affinities. Many of the free Polycystina (?) taken in the towing-net, 
such as Distyocha, should be referred to the Thalassicollidce. He suggests 
the following arrangement of the 
Polycystina. 
Rhizopoda furnished with a siliceous spicular or fenestrated h’amework. 
' Growth of ( Sin.pleorcoutiuuo«s...,| 
sarcode 1 By conceutric accessions | 
, ( •' I Astro7)ima. 
M. Ponton (^The Beginning, its When and its How’) figures many 
forms of Foraminifera (pi. A), Polycystina (pis. B-E), and spikes of ditto 
(pi. Q). 
W. K. Parker, T. R. Jones, and H. B. Brady, On the Nomenclature 
of the Foraminifera,^' Ann. N. II. (4) viii. pp. 145-179, 238-266, pis. 8-12, 
review 158 recent and fossil species founded by D’Orbigny, in Ann. Sc. Nat. 
1826, vol. vii., on the figures in Soldani’s ‘ Testaceographia ac Zoophyto- 
