fe) THE NORTHERN MICROSCOPIST. 
OUR BO@K SHELF, 
A Manual of the Infusoria. W. SavitiE KEntT, F.LS., F.Z.S., 
F.R.M.S. London: David Bogue. 1880. Part I., 144 pp., 9 
plates, including frontispiece. Part II., 144—288 pp., and 8 
plates. 
Tuts long looked for work has at length made its appearance, and 
we think its contents and general style will have satisfied all 
subscribers. ‘Two parts out of the six have been issued, and the 
remainder announced to appear monthly till the work is completed, 
and if the same care is bestowed upon the succeeding parts as 
upon the first two, we have no hesitation in styling it a book which 
no microscopist’s library should be without. 
The contents of the first part reach four chapters, the first of 
which is introductory, and gives a general history of Infusoria from 
the time of their discovery by Leeuwenhoek in 1675 up to the 
present day. ‘This chapter is exceedingly interesting, showing as 
it does how our discoveries may be looked upon two hundred years 
hence. Ehrenberg’s work is noticed at some length, and mention 
is made of the numerous errors propagated by that observer. 
There are several works which have been published on this 
subject, but all are now out of date, and the most recent of them, 
viz., ‘‘Pritchard’s History of the Infusoria,” which was published in 
18 34 (the fourth edition appearing in 1861), was chiefly a compila- 
tion of the work of others, and contained accounts of organisms, 
which must certainly now be expunged from the list of true 
Infusoria. 
Chapter II. treats of “the Sub-kingdom Protozoa,” and on p. 
36 is given in a tabular form the sections, classes, orders, families, 
and typical genera of this sub- kingdom. Chapter III. is a disserta- 
tion on the nature and organization of the Infusoria which the 
student will do well to study carefully. The information contained 
in this chapter is worth the price charged for the whole part, and 
in order to make this clear we give the sub-headings, which show 
that the care taken by the author to make his work complete has 
been of no mean character: Cuticular elements or Ectoplasm— 
Internal elements or Endoplasm—Excreted elements—Encystment 
—Locomotive and prehensile appendages—Oral apertures or 
Cystostomata—Anal apertures or Cytopyge—Contractile vacuole 
or vesicle—Nucleus or Endoplast—Nucleolus or Endoplastule— 
Coloring matters—Accessory structures—Amylaceous corpuscles— 
