88 THE OCEAN WORLD 



tentacle. Beneath this is a layer of granules, or rather a gelatinous 

 membrane, through the substance of which minute granules are scat- 

 tered without any very definite arrangement ; from hence arises a 

 network of very delicate fibrils, whose meshes are not more than the 

 three-hundredth part of an inch in diameter, which gradually pass 

 internally the reticulation becoming more and more open into 

 coarser fibres, taking a convergent direction towards the stomach 

 and nucleus. All these fibres and fibrils are covered with minute 

 granules, which are usually larger towards the centre." 



Prof. Huxley is inclined to think, from all he has observed, that 

 the animal has a definite alimentary cavity, and that this cavity has 

 an excretory aperture distinct from the mouth. These facts, together 

 with the existence of a dental armature, greatly increase its affinity to 

 such forms as Colpoda and Nassula among the Infusoria, while the 

 general absence of cilia over the body, and the wide differences 

 in detail, would require the constitution of at least a distinct family 

 for this singular creature. 



Surriray discovered the Noctiluca while investigating the cause of 

 the phosphorescence of sea water at Havre, where it was abundant 

 in the basins, sometimes in such abundance as to form a scum on 

 the surface of the water of considerable thickness. " This singular 

 little creature," says M. Fre'dol, " offers here and there in its interior 

 certain granules, probably germs, and also luminous points, which 

 appear and disappear with great rapidity, the least agitation bringing 

 out their lustre." The Noctiluca are so abundant in the Mediterranean 

 and on many parts of our English coasts, that in a cubic foot of sea 

 water, which has been rendered phosphorescent by their presence, it is 

 calculated that there may exist about 25,000. We now come to the 



INFUSORIA. 



Of this very interesting group a large proportion are marine, and 

 very many numerous varieties of them are found in the British seas. 

 In their minuteness and variety they almost baffle the attempts of 

 naturalists to classify them. 



We find both fresh and salt water inhabited by legions of these 

 active, ever-moving beings, of dimensions so small as to be inappreci- 

 able to the naked eye ; these minute creatures are disseminated by 

 millions and thousands of millions in the great deep, and all know- 

 ledge of them would have escaped us, as they escaped the knowledge 

 of lormer scientific men, but for the discovery of the microscope, the 

 sixth sense of man, as it has been happily called by the poet and 



