33 



In a recent state an abundance of mucus escapes on pressure from their outer 

 pores, according to the observation of Cuvier, in the genus Octopus ; and he 

 found also that air or injection thrown into the vessel readily escaped from the 

 follicles into the pericardium, and that air blown into the pericardium {cavite 

 veineuse) frequently filled the veins. Professor Grant has observed, that in a 

 living Calamary {Loligo sagittata, Lam.), these glandular "parts of the veins 

 exhibited a remarkable peristaltic motion, which continued as long as any other 

 motions of the body*." I have injected the arteries of these follicles in the 

 Cuttle-fish, which ramify in a beautifully minute arborescent form upon them, 

 and testify by the size and number of branches to their glandular nature. 



In all the Cephalopods the folUcles are appended to that part of the vascular 

 system which terminates the greater, or commences the lesser circulation. But 

 besides their use as connected with the respiratory system, and effecting changes 

 in the blood itself, either by way of depuration or addition, I am induced to 

 believe from the following considerations that they also perform a secondary 

 function, which has not hitherto been attributed to them. 



The Cephalopods of the higher order have a power of locomotion superior to 

 all other MoUusks, and can vary their elevation in the water at will. The Pearly 

 Nautilus also, though in general dwelling in the deep, has the power of rising 

 and floating on the surface, as appears from the testimony of Rumphius, and 

 the circumstances connected with the capture of the present specimen. These 

 changes of position must obviously produce great alterations in the degree of 

 pressure which the animals have to sustain from the surrounding medium ; and 

 the fluids contained in their sanguiferous system must, of course, suffer con- 

 siderable and corresponding variations of expansion. We must suppose also 

 that their respiration, or the transmission of the blood through the gills, will 

 be more or less rapid, both according to the distance from the surface at which 



aurait a se subdiviser, pour ^prouver, au travers des parois du corps spongieux, I'influence de I'^Mment 

 ambiant ; ou, ce qui reviendrait au fond k-peu-pr^s au meme, des canaux excr^teurs, par lesquels le 

 corps spongieux verserait dans la veine quelque substance qu'il n'aurait guere pu lui-meme extraire 

 que de cat flement ambiant ; ou, enfin, des £monctoires, par le moyen desquels le sang se d^barrasserait 

 de quelque principe qu'il verserait au dehors par les pores et les replis ext^rieures des corps spongieux." 

 Cuvier, Mem. sur le Pouipe, p. 19. 



* Edinbiu-gh Philosophical Journal, xvi. p. .314. 



F 



