. 
1381.] Recent Literature. 463 
of technical terms in the proper places in the text. Every reader 
or student should be expected to possess and exercise a memory 
of sufficient strength to enabie him to keep in mind the meaning 
of the terms used and explained in the text. A glossary which 
merely re-describes or re-defines is a standing temptation to 
slovenly reading or study, and in the opinion of the writer, ought 
never to find a place in ordinary text-books designed for students. 
he mechanical execution of the book, in the printing and the 
binding, is neat, and the typographical errors are notably rare. 
Professor Underwood deserves and will receive the thanks of the 
many fern-lovers in the country for giving us this book.—C. Z. B. 
Kent’s MANUAL OF THE INFUSORIAJ—This will, when com- 
pleted, be the only available manual of the Infusoria in the En- 
glish language, the old one by Prichard being superannuated, in- 
cluding as it does diatoms, desmids and Protozoa of all classes. 
We have looked forward with much interest to the appearance of 
Mr. Kent’s work, and owe to the kindness of a friend an oppor- 
tunity of looking over three parts which have already been pub- 
lished. It is a much more valuable, extensive and important 
work than we expected to find, and we can recommend it to mi- 
Croscopists and to the general student as in every way excellent, 
both in its scientific execution, its fullness of detail, its elaborate 
and comprehensive introductory portions, which will be read with 
much interest and profit, and the variety and excellence of its 
os pa the latter of course being an essential feature of such 
work, 
The first chapter gives the general history of the Infusoria from 
the time of their discovery, by Leuwenhoek, in 1675, to the year 
1880. In the second chapter the sub-kingdom Protozoa is dis- 
cussed in a way calculated to bring out clearly the relations of the 
Infusoria to the other classes. Mr. Kent does not regard the 
regarinide as entitled to constitute a distinct class of Protozoa, 
of Structure with relation to the latter as is presented by the 
Opalinide with respect to the ordinary Ciliata.” He divides the 
1 
G ~ Manual of the Infusoria : including a description of all known Flagellate, 
iliate, and Tentaculiferous P t British and foreign, aR ee tofth Organi 
— and Affinities of the Sponges. By W. Savitte Kent, F, L. S., etc. London, 
wid Bogue, 1880, Parts 1 to Ill, each tos. 6d, 8°. tk 
