1865.] Kollikcr's Outlines of the Lowest Forms of Life. 5S5 



bine all the attractions of living and moving beings, and their interest 

 is by no means confined to their external coverings. Some of them 

 resemble globular groups of pearls, with a brilliant central gem of moro 

 solid consistency, the whole emitting bright rays (pseudopodia) in every 

 direction ; and on examining the constituent globules, each one is found 

 to be more or less highly organized. Others are still more beautiful 

 and interesting ; one, for example, resembles a conical Japanese hat of 

 honeycombed silex, bristling all round the rim and on the apex with 

 spikes, and harbouring in the crown of the silicious fabric the multi- 

 cellular animalcule, from which innumerable rays are projected. 

 Another is a perfect hollow silicious sphere of filagree, also honey- 

 combed, and in the centre floats a beautiful sun, whose rays penetrate 

 the open framework of the globular case ; and a fourth, more exquisite 

 perhaps than any of the preceding, might serve as one of the insignia 

 of some noble order, for it presents the appearance of a jewelled star. 

 The central portion is the hyaline animalcule resembling a globular 

 pearl in appearance, from which project silicious rays, some lance- 

 shaped, others straight, and all meeting within the central globe. 

 There are many more such forms, varying in the shape of the central 

 soft portions, or in that of the radiating silicious skeleton, or of the 

 surrounding casework, but all are more or less graceful and elegant, 

 and the delineations of them in the present work have only to be seen 

 to render them eager objects of search and favourite subjects for inves- 

 tigation. 



Little seems yet to be known of the physiological attributes of the 

 Radiolarise, and for what has been revealed in this respect, the student 

 will find himself indebted to Ehrenberg, T. H. Huxley, J. Miiller, 

 Claparede and Lachmann, A. Schneider and E. Hackel. An account 

 of the minute anatomy of the sponges concludes this work on the 

 Protozoa ; and these are described with great clearness, justice being 

 rendered to all observers who have contributed to our knowledge of 

 their Natural History. 



The opinions of Professor Kolliker on all matters connected with 

 microscopic anatomy and micro-zoology, are entitled to great consi- 

 deration, and it will be interesting to some of our readers to hear his 

 opinions on two or three debated topics. After carefully reviewing 

 the question of the distinctive characters of the lowest plants and 

 animals, he comes to the conclusion that there is no well-defined 

 distinction between them. Again, both as bearing upon this question, 

 and as a matter of interest to psychologists, it may be mentioned 

 that he believes the Infusoria to possess a will, for in describing how 

 the cilia of Paramecium bursaria may be excited to movement by tho 

 action of acetic acid after they are separated from the body, he says, 

 this shows that although these organs are generally under the controul 

 of the animal's will, they are not necessarily so (" was zugleicb zeigt 

 dass diese Organe wenn auch gewoknlich, doch nicht nothwendig 

 unter dem Willeneinflusse des ganzen Organismus stehen." — p. 10). 



As the author cites the presence of Cilia in the lowest plants, as 

 well as the lowest animals, as part of the evidence to prove that it is 

 impossible to distinguish one from the other, we have the choice 



