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hexagonal network, so that the [lore appears to lie
at the hottom of a hexagonal pit. At each angle of
this hexagon the crest gives otf a delicate flexible
calcareous spine, which is sometimes four or five
times the diameter of the shell in length. The
spines radiate symmetrically from the direction of the
centre of each chamber of the shell, and the sheaves
of long transparent needles, crossing one another in
different directions, have a very heautiful effect.
The smaller inner chambers of the shell are entirely
tilled with an orange-yellow granular sarcode ; and
the large terminal chamber usually contains only a
small irregular mass, or two or three small masses
run together, of the same yellow sarcode stuck
against one side, the remainder of the chamber
being empty. No definite arrangement, and no approach
to structure, was observed in the sarcode ;
and no differentiation, with tlie exception of bright
yelloAV oil-glohules, very much like those found in
some of the Badiolarians, which are scattered apparently
irregularly in the sarcode ; and usually one
very definite patch of a clearer appearance than the
general mass, coloured vividly Avith a carmine solution
; aud the presence of scattered particles of
bioplasm Avas indicated by minute spots here and
tliere throughout the Avhole substance, Avhicli
received the dye.
AYheu tlie living Glohigerina is examined under
very favourable circumstances, that is to say, when
it can he at once placed under a tolerably high power
of the microscope in fresh still sea-water, the sar-
codic contents of the chambers may he seen to exude
gradually through the pores of the shell, and spread
o u t u n t i l i t fo rm s a k in d o f f lo c c u le u t f r in g e r o u n d
th e sh e ll, f i l lin g u p th e sp a c e s am o n g th e r o o t s o f th e
sp in e s a n d r is in g u p a l i t t l e Avay a lo n g th e ir le n g th .
T h is e x t e r n a l c o a t in g o f sa r c o d e is r e n d e r ed very
v i s ib le b y th e o i l- g lo h u le s , w h ic h a r e o v a l a n d fille d
Avith in t e n s e ly - c o lo u r e d s e c o n d a r y g lo b u l e s , a u d a r e
d r aw n a lo n g by th e sa r c o d e , a u d m a y b e s e e n w i th
a l i t t l e ca r e f o llo w in g i t s sp r e a d in g o r c o n t r a c t in g
m o v em e n t s . At th e s am e t im e a n in f in i t e ly d e lic a t e
sh e a t li o f sa r c o d e c o n t a in in g m in u t e t r a n sp a r e n t
g r a n u le s b u t n o o i l- g lo b u l e s , r is e s o n e a c h o f th e
sp in e s to i t s e x t r em it y , a u d m a y h e s e e n c r e e p in g Aip
o n e s id e a u d doAVu th e o th e r o f th e sp in e w i th th e
p e c u lia r Jloiving m o v em e n t Avith Avhich Ave a r e so
fam ilia r in th e p s e iid o p o d ia o f Gromia an d o f th e
B a d io la r ia u s . If th e c e ll in w h ic h th e Glohigerina
is f lo a t in g r e c e iv e a su d d e n s lio c k , or i f a d rop o f
s om e i r r it a t in g f lu id b e a d d e d to t h e Avater, th e
w h o le m a s s o f sa r c o d e r e t r e a t s in t o th e s h e l l w i th
g r e a t r a p id ity , d r aw in g th e o il- g lo h u l e s a lo n g Avith
i t , a n d th e o u t l in e o f th e su r fa c e o f th e s h e ll a u d
of th e h a ir - lik e sp in e s i s le f t a s sh a rp a s b e fo r e
th e e x o d u s o f th e sa r cod e .
Major Owen {op. cil.) has referred the Glohigerina
Avith spines to a distinct species, under the name of
G. Ursula. I am inclined rather to helieve that all
Glohigerince are, to a greater or less degree, spiny
when the shell has attained its full development. In
specimens taken with the tow-net the spines are very
usually absent; but that is probably ou account of
their extreme tenuity; they are broken off by the
sliglitest touch. In fresh examples from the surface
the dots indicating the origin of the lost spines
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