530 Scientific Intelligence. 



extent, the individual properties, especially the optical ones, of 

 the various important and accessory rock minerals are compactly 

 described. The main body of the work which follows consists 

 of tables arranged according to a definite plan, optical characters 

 being used, somewhat in the way in which the properties of 

 plants are classified in botanies, for the determination of the 

 species. Under the heading of each mineral in the table its 

 important crystallographic and optical properties are given, and 

 tests of various kinds are suggested for its discrimination from 

 others, with which it might be confused. Although the book -is 

 printed and bound in the ordinary manner, an arrangement for 

 cutting the edges is indicated, which, if followed, will facilitate 

 the use of the tables. 



A large amount of time and labor has evidently been expended 

 in the preparation of this volume and great care used in col- 

 lecting and tabulating the large number of details it contains. 

 For all those who are seriously engaged in the study of rock 

 sections it will prove of great service. In the few weeks that 

 have elapsed since its publication the writer has found it an 

 efficient aid in the petrographical laboratory, especially with 

 more advanced students. It is well printed and durably bound, 

 and is a credit to both author and publisher. l. v. p. 



III. Miscellaneous Scientific Intelligence. 



1. A Monograph of the British Annelids. Vol. 2, Part 1 . Poly- 

 chceta : Nephthydidoe to iSyllidce ; by Williaji Cakmichael Mc- 

 Intosh. Pp. viii, 232, quarto, with 22 plates of which 8 are colored ; 

 London 1908. (The Ray Society.) — All students of marine zool- 

 ogy will welcome the appearance of this new volume continuing 

 the series of beautiful monographs by the well-known authority 

 on British Annelids. The first part of this work dealt with the 

 Nemerteans, and appeared about 35 years ago. It is hardly 

 necessary to state that the present book exhibits the same thor- 

 ough study of the species which has characterized the other 

 portions of the work. Whenever sufficient material could be 

 obtained, each species has been subjected to detailed anatomical 

 examination, and such structures as are of importance to the 

 systematist illustrated by well-executed drawings. The habits 

 of the species and such embryological data as are available have 

 been given in each case, and finally, the extensive synonymy of 

 the species will be appreciated by every worker in the group. 



The author retains the older system of classification and in- 

 cludes in this part the families Nephihydidce, Phi/llodocidce, Hes- 

 ionidce, and Syllidce, which are represented in British waters by 

 30 genera and a much larger number of species. A discussion of 

 the evidence as to the relationships and systematic position of the 

 families is promised for the final part of the work. 



