320 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
suggests the sculpturing of diatoms, and consists of exceedingly delicate 
and hardly recognisable primary chambers or cells between the two 
closely apposed lamellae. In Cyttarocylis cassis there is a coarse 
irregular reticulation, but higher magnification shows in each area a 
number of minute and delicate cells. In Ptychocylis ( = Cyttarocylis 
semireticulata Biederm., &c.), the external shell-lamella bears reticulate 
ridges, and there are fine primary cells between the lamellas. In the 
littoral Tintinnopsis the wall has refractive portions, and in part extrinsic 
bodies, in the pelagic Codonopsis these are absent ; but in both there 
is a primary and secondary figuration. The author also deals with 
the question of distribution, distinguishing eupelagic and hemipelagic 
forms. 
New Genus of Astrorhizidse.* — Mr. A. Vaughan Jennings describes 
Bhaphidoscene conica g. et sp. n., which was found adherent to Botellina 
labyrinthica Brady in some ‘ Porcupine ’ dredgings. The shell consists 
of a tent-shaped structure of closely-set sponge-spicules, and measures 
about 1/25 in. in height. The form appears to be an extremely simple 
type of Foraminifer, building a protective roof of sponge-spicules. In 
.habit it is the equivalent of simple forms of Nubecularia in the Porcel- 
lanea, and of Placopsilina and Webbina in the Lituolidae. 
True Nature of “ Moebiusispongia parasitica.”! — Mr. A. Vaughan 
Jennings points out that this organism,* which Prof. Martin Duncan 
found in some sections of Carpenteria rhapTiidodendron Mob., and supposed 
to be a parasitic calcareous sponge, is really a Foraminifer, a species of 
Bamulina , probably B. globulifera. 
Shell-making in Ehizopods.f — Dr. L. Rhumbler finds that some 
freshwater Rhizopods ( Difflugia pyriformis , D. constricta , &c.) lose the 
power of increasing the size of their tests after the shell-formation which 
occurs during gemmation. In other words, there are some which have 
no secondary shell-growth. Others, like Arcella , show secondary growth. 
The author gives a detailed account of Cyphoderia margaritacea. As 
regards the conjugation, he observed that an animal with a nucleus just 
divided frequently united with one whose nucleus had not for a long 
period undergone division. He goes on to discuss the phylogeny of 
shell-formation and of budding in the Testacea. Thus he suggests the 
following four groups, established in relation to their shells : — 
(1) Nuditestidse, with naked shell, of unlimited growth, where the 
shell begins by the constriction of the adult mother-shell into two, e.g. 
Lieberhuhnia , Diploplirys. 
(2) Adjungentidse, with extrathalamous accumulation of the test- 
material, and inversion of this in the formation of the test, e. g. 
Difflugia (?) amphora , var. minor, Pseudodifflugia amphitrematoides. 
(3) Revolventidse, with intrathalamous accumulation of test-material, 
and inversion of this, Cyphoderia. 
(4) Protrudentidse, with intrathalamous accumulation of test- 
material, without inversion, e. g. Euglypha , Difflugia urceolata, &c. 
Had we space, there is much else that is noteworthy to be recorded in 
* Journ. Linn. Soc. Zool., xxv. (1896) pp. 320-1 (1 pi.). ~ 
f Tom. cit., pp. 317-9. 
J Zeitschr. f. wiss. Zool. ; lxi. (1895) pp. 38-110 (2 pis. and 10 figs.). 
