Revieivs — A Guide to Fossil Invertebrate Animals. 41 



Canada, and IS'ewfoiindland, and has also further examined those 

 derived from rocks of the same age in Britain and Scandinavia. In 

 some of the American rocks very diminutive specimens, representing 

 the early stages of growth of these Trilobites, have been preserved, 

 and from them the author has endeavoured to trace out their lines of 

 development. These fresh discoveries have also provided materials 

 for a thorough revision of the classification of the group, which is 

 worked out in considerable detail. The author states that with the 

 exception of forms referred to Nevadia and Callavia, in which a small 

 anterior glabellar lobe is present, the variations in the characters of 

 the cephalon throughout the group are only of specific value ; and 

 as the pygidium also is essentially similar, the basis for generic 

 separation mainly depends on modifications of the thorax. Five 

 new genera, Nevadia, Pcedumias, Peachella, and Wanneria, are 

 introduced, and many new species are described and figured on the 

 twenty-two plates. The use of the family term Mesonacidse in 

 preference to Olenellidae is justified on the ground that the former 

 has the priority, and that the genus Mesonacis is more typical of the 

 family than Olenellus. 



V. — A GtriDE TO THE Fossil Inveetebkate Animals in the Depart- 

 ment OF Geology and Paleontology in the British Museum 

 (E'atuhal History). Second Edition. 8vo; pp. x, 184, with 7 plates. 

 Printed by order of the Trustees. London, 1911. Price Is. 



rnHE first edition of this admirable guide was published in 1907. 

 X In the present one may be noticed the omission of a separate 

 account of the Koenig and Gilbertson Collections (p. 9), owing to the 

 specimens having been dispersed among the systematic series. The 

 addition of the Archaeocj'-athinse (p. 42). A revised account of the 

 Cirripedia (p. 94). Several alterations due to the rearrangement of 

 the Brachiopoda (p. 114). An Appendix (p. 117) noting recent 

 additions to the exhibited series of Mollusca. Fig. 41 is an original 

 figure of the under-surface of Eurypterus Fischeri. Fig. 49 is from 

 a new drawing of Protocarcinus longipes. Fig. 65^; represents 

 a Senonian species of Memhranipora. In making some of these 

 alterations the author, Dr. F. A. Bather, acknowledges the help of 

 Dr. W. T. Caiman, Messrs. E. B. Newton, W. D. Lang, and T. H. 

 Withers. The figures throughout the Guide are admirable. 



VI. — Geundztjge dkr Palaontologie. — The preparation of a new 

 ■edition, the third, of this well-known textbook of Palaeontology of the 

 late Professor K, A. v. Zittel, has been carried out by Professor Dr. F. 

 Broili, of Munich, whose friendly help in correcting the proofs of the 

 two earlier editions was gratefully acknowledged by the author of the 

 work. The first part of the present edition, comprising the Inverte- 

 brata, is a volume of 607 pages, with 1,414" text-figures and a separate 

 index. About seventy of the figures are new, and to a large number 

 of the older cliches further explanatory letterings have been added. 

 Dr. Broili has endeavoured to incorporate in the volume all the recent 

 discoveries in Invertebrate Palaeontology ; references are given to the 



