XIV SCIENCE PROGRESS. 



the Cryptogams in this volume, and it forms indeed an admirable intro- 

 duction to a study of these plants. 



The treatment adopted is methodical, and the essential points of con- 

 trast and comparison between the different groups are well brought out. 

 It is satisfactory to notice that that highly specialised form, Marchantia, 

 which has usually had to do duty as the representative of the Hepaticae 

 has here given way to a more generalised type as seen in Pellia. We 

 cannot, however, suppress a feeling of regret that space did not admit 

 of a little more recognition being accorded to the foliose of Liverworts. 

 Not only are they exceedingly numerous as regards species, but they 

 are also very rich in interesting forms. 



The Algae and Fungi strike us as being very well done, and we are 

 glad to see that UlotJirix occupies the prominent position to which its 

 own intrinsic importance and the ease with which it can be obtained 

 justly entitle it. 



The clear summaries and the numerous illustrations increase the 

 value of one of the very best elementary text-books of Botany which have 

 appeared for many a year. 



Worms, Rotifers and Polyzoa. Being Vol. II. of the Cambridge 

 Natural History. Edited by S. F. Harmer, M.A., and A. E. 

 Shipley, M.A. " Flatworms and Mesozoa," by F. W. Gamble, 

 M.Sc. " Nemertines," by Miss L. Sheldon. "Thread Worms and 

 Sagitta," by A. E. Shipley, M.A. "Rotifers," by Professor Marcus 

 Hartog, M.A. " Polychoet Worms," by W. B. Benham, D.Sc, 

 Hon. M.A. Oxon. " Earthworms and Leeches," by F. E. Beddard, 

 M.A., F.R.S. "Gephyrea and Phoronis," by A. E. Shipley, M.A. 

 "Polyzoa," by S. F. Harmer, M.A. London: Macmillan & Co., 

 Limited, i8g6. 



The death knell of the " Class Vermes" has long been rung, and 

 under orderly arrangement, consequent on extended and detailed investi- 

 gation, the vast accumulation of animals which in the last generation 

 were relegated to that assemblage have been resolved into a series of 

 well-defined groups which form the subject matter of the greater portion 

 of this volume. In effecting this re-arrangement none have been more 

 active in our own country than Messrs. Beddard, Benham, Gamble, 

 Harmer, and Shipley — each a foremost worker in his own department ; 

 and when it became known that these gentlemen were to co operate 

 with Miss Sheldon, a recognised investigator of allied forms of life, and 

 with Professor Hartog, in the authorship of the volume now before the 

 world, expectation ran high, in the hope of a work which would do 

 credit to English zoologists, and would be found to contain something 

 beyond the hum-drum colourless take-all-and-do-as-you-like-with-it re- 

 capitulation of ill-assorted details, familiar in a certain class of continen- 

 tal text-books. It was to be expected that that judicious selection of 

 facts which is the highest function of a scientific author would be brought 



