441 Bibliographical Notices, 



more at length into this subject. We may however observe that 

 none of the opposers of Ehrenberg's views agree in what they see ; 

 we are therefore still inclined to place confidence in his observations, 

 trusting that this important subject will soon be thoroughly investi- 

 gated. Speaking of the superiority of modern microscopes, Prof. 

 Jones observes, that a few years ago some Infusoria, now distinctly 

 proved to be covered with cilia, were looked upon as being absolutely 

 destitute of locomotive organs, for instance, Volvox globator ; we 

 would however remind the author, that if a great deal depends on the 

 goodness of the instrument, a vast deal more depends on the long- 

 practice and manipulation of the observer ; and no better proof of this 

 fact can be adduced than that this Infusorium, usually considered as 

 a simple animal, even in the present work, is a conglomeration of 

 several hundred individuals. We have inserted the paragraph re- 

 specting this remarkable animalcule from Ehrenberg's large work 

 on Infusoria among the miscellaneous articles of the present number. 

 Trichina spiralis, hitherto found only in the human body, has been 

 discovered by Dr. Siebold in several animals and birds, and even in 

 Scarabaus stercorarius* . Mr. Jones is also led into error with respect 

 to the occurrence of the eggs of Cristatella in a fossil state by Tur- 

 pin's mangled description of the fossil specimens of Xanthidium, dis- 

 covered by Ehrenberg in the Feuerstein of Delitzsch, and forwarded 

 by him to the French Academy. The Xanthidium is a decided In- 

 fusorium, and Ehrenberg, in a paper respecting this misstatement 

 of Turpin, which has however probably escaped the attention of 

 Prof. Jones, clearly proves that it is no egg, and moreover several 

 fossil species of Xanthidium occur in the recent state which had 

 been figured previous to their discovery in flint. Besides, whoever 

 has examined the egg of Cristatella and also living Xanthidia will be 

 convinced of their distinctness. Those who have not may compare 

 the beautiful drawings of the various Xanthidia occurring in the 

 flints of the chalk, illustrating the P^ev. B. Reade's paper at p. 191 of 

 the 2nd volume of the ' Annals', with the excellent copy of Turpin's 

 drawing of Cristatella Mucedo. Dr. Farre's beautiful discoveries 

 have been consulted with respect to the Ciliobrachiate Polyps, Milne 

 Edwards for the Flustra?, and Strauss Durchheim, Duges, and J. Mid- 

 ler for the insect tribe. We are convinced that no work will have 

 tended more to diffuse a love for zoological science and comparative 

 anatomy in this country than that before us, and we feel called upon 

 to express most decidedly our sense of the obligations which its 

 learned author has conferred upon the English public by placing be- 

 * Wiegmann's Archiv, part IV. for 1838, p. 312. 



