1880.] 



MICROSCOPICAL JOEJEKAL. 



23r 



great cost, which practically places 

 it beyond their reach. The three 

 parts cost over $71. However, Mr. 

 Kent has embodied the knowledge 

 of the Infusoria which we possess 

 in the work of which the first part 

 is now before us. This part con- 

 tains one hundred and forty-four 

 quarto pages of clear text, and eight 

 full-page plates engraved on metal 

 from drawings by the author. 



The text is descriptive, and very 

 readable, even to persons who do 

 not use the microscope. The iirst 

 chapter is devoted to a general his- 

 tory of the infusoria from the time 

 of their discovery by Leewenhoek, 

 in 1675, to the year 1880. In this 

 chapter we find some interesting 

 reminiscences of Leewenhoek, in- 

 cluding his first account of his dis- 

 coveries in the form of a letter 

 dated October 9th, 1676. We can- 

 not refer to many other names 

 associated with the history of the 

 subject, some familiar to all mi- 

 croscopists, as Ehrenberg, Dujardin, 

 Yon Siebold, Pritchard, and others 

 not so well-known, but must pass 

 on to the second chapter, which 

 treats of the sub-kingdom Pro- 

 tozoa. The text is supplemented 

 by a table giving the sections, 

 classes and other divisions of the 

 Protozoa, which may be stated to 

 embrace all those forms which we 

 recognize as Rhizopoda, Flagellata, 

 Ciliata and Tentaculifera. Of these 

 the Infusoria, as limited by the 

 author in this work, embraces all of 

 these forms exclusive of the Rhizo- 

 poda, and two orders of the Flag- 

 ellata — the Mycetoza and the 

 Spongida. Owing to the close 

 relations of the Spongida to some 

 of the Flagellata, however, the 

 fifth chapter of the work is devoted 

 to a brief consideration of the 

 nature and affinities of the sponges, 

 many species of which are figured 

 in the plates. 



We have been particularly in- 

 terested in one or two paragraphs 

 which relate to the distribution of 

 infusorial spores upon blades of 

 grass, hay, etc., for the reason that 

 they corroborate some observations 

 made by us during the past Sum- 

 mer, which, however, were not re- 

 garded as perfectly reliable. It 

 appears from Mr. Kent's observa- 

 tions that the blades of grass are 

 loaded with the germs of infusorial 

 life, which only await the vivi- 

 fying influence of rain or dew 

 to afford the microscopist a world 

 of living forms. In examining 

 the hairs of growing blades of 

 corn last Summer, we noticed the 

 presence of numerous infusoria, 

 which we thought at the time came 

 from the leaves, and now we are 

 positive that it was true. 



To enable the reader to form an 

 idea of the author's style of writing, 

 the following quotation will sufiice : 



" With the Infusoria we encoun- 

 ter not only the as yet known most 

 minute, but also the most ele- 

 mentary and simply formed pro- 

 ductions of the Creator's handiwork, 

 though, for all that, none the less 

 complete and excellently finished. 

 Among the Infusoria, making a 

 free adaptation of the admirable 

 thesis propounded by the illus- 

 trious Oken, we find in their prim- 

 eval shape the very bricks and 

 mortar out of which the entire 

 superstructure of the oi'ganic world 

 has been erected. * * * Tlie divine 

 fiat ' Dust thou art, and unto dust 

 thou shalt return,' thus received 

 unconsciously at the hands of Oken 

 a practical and truly remarkable 

 illustration. Finally, among the 

 world of Infusoria we arrive at 

 that dim boundary line, too subtle 

 and obscure for arbitrary definition, 

 that separates, or more correctly 

 blends into one harmonious whole, 

 the two dej)artments of the animal 



