THE LOWER FOEMS OF LIFE. 



the surface of the sea. It is not until placed under the microscope 

 that they present the appearance as shown in the figures. 



Fig. 79. Fig. 80. 



Fig. IS.Physematium Millleri (magnified 15 diam.) The whole animal dead. 



Fig. SQ.Collosphcera Huxleyi (magnified 300 diam.) A whole colony alive. In the middle 

 a large alveolus, surrounded by a sarcode net, within which are smaller alveoli. In the 

 central capsule, which represents the parent animal, there are observed one or two balls 

 of oil. The larger cells covered with a transparent shell, the smaller ones naked. Out- 

 side the young brood, among the rays of the pseudopodia, a number of small yellow 

 bodies, supposed to be germs, are observed. (All after Kolliker.) 



Kolliker divides the Radiolaria, as far as they are at present 

 known, into thirteen genera and many distinct species, and their 

 discovery, as I stated before, is quite of recent date. Their great 

 beauty will, no doubt, make them a favourite subject of investiga- 

 tion with the histologist. They form a ready transition to the last 

 and, according to Kolliker, the highest division of the Protozoa, 

 which I now proceed briefly to notice, viz. : 



THE SPONGES. 



I say, to notice briefly, because we have a recent classical and 

 exhaustive work upon the subject, to which naturalists can 

 readily refer, viz., " The Monograph of the British Spongiadae" by 

 Dr. Bowerbank, the first volume of which has been published by the 

 Bay Society. The subject has also been illustrated by many papers 

 in our popular publications. 



But I do not wish for a moment to detract from the great scientific 

 interest which is attached to the study of the Sponges. On the 

 contrary, I think there are few objects in natural history whose life 

 is better worth recording than that of a Sponge. 



