67 
explanation of plate 34. 
«• rile Heart. 
A bristle passing from the pericardium through the 
^ membranous siphuncle laid bare. 
nstles passing from the pericardium through the 
onhces of communication with the Branchial cham- 
ber. 
d. d. d. Follicles communicating with the Branchial 
Arteries.* 
'd. 'd.^d. 'd. Pericardial septa, forming thin muscular 
receptacles of the follicles. 
e. The Branchiae. 
J- The Branchial Chamber. 
8 - The Funnel, or Branchial outlet, 
m The infundibular valve. 
i- The digital processes. 
The Gizzard. 
The Ovary. 
ni. The mantle dissected off’, 
m rile membranous siphuncle. 
0. The siphuncular artery. 
P- ^ The Boundaries of the Pericardial cavity. 
ortion of the Siphuncle between the Pericardium and 
first transverse plate of the shell.f 
o 
Llo ®''PPOses that these follicles discharge the impurities 
to the Bra°^ V ^oricardium, when there is no access of water 
fis shell the time that the animal is contracted within 
‘•‘rouffi, lu O'^erflowings of this pericardial fluid may pass out 
^ gj the orifices marked by the bristles, c. c. 
hatteuer **^**f'^ Portion or neck of the Siphuncle, has the form of a 
oardivijij • Parietesof the same substance as the Peri- 
thisnggv’.''^ *^0 the animal expands itself at the bottom of the sea, 
a*id ovar ** P*°^ably closed b}' the lateral pressure of the gizzard, k, 
the peri^^'a' instead of a valve to prevent the return of 
'rater Siphuncle. At such times, the deep-sea 
tend? ““ exterior of the Pericardium, 
O'ltial a ° pericardial fluid into the Siphuncle ; but as an 
®ount of pressure is applied simultaneously to the Ovary and 
