REVIEWS 
Grundziige der Paléontologie. Von Kart A. VON ZiTTEL. II. Abtei- 
lung. Vertebrata. Neubearbeitet von F. Brom, E. KoKxen, 
M. Scutosser. Miinchen und Berlin, torr. Pp. 508. 
Zittel’s Handbuch der Paléontologie, the publication of which was 
completed nearly twenty years ago, marked the beginning of a new 
epoch in paleontology. And his compendium, or Grundziige, the first 
edition of which was published in 1895, the English edition by Eastman 
in 1900-1902, has been of the greatest service to all students of the 
science. But the years that have elapsed since these editions appeared 
(and the English edition did not include the mammals) have greatly 
impaired their usefulness. The science of paleontology, and especially 
vertebrate paleontology, is progressing with such rapidity that even a 
few years leaves any text behind. 
It is very doubtful whether other editors could have been found as 
competent for the present edition as Broili, Koken, and Schlosser. 
Additions and changes have been made with great conservatism, some 
will think with undue conservatism; but, in the opinion of the reviewer, 
conservatism here is a commendable fault, if fault it be. It will be 
time enough to accept the many new orders and suborders of verte- 
brates, the many changes in classification, which have been proposed 
in recent years when they shall have stood a longer test. In the past 
history of science the majority of such innovations are ultimately 
rejected. 
Of the fishes, treated by Koken, six subclasses are accepted: the 
Placodermi, or Agnatha, Elasmobranchii, Holocephali, Dipnoi, Arthro- 
dira, and Teleostomi. As regards the Arthodira the relations of which 
have been the subject of no little discussion in recent years, Koken rejects 
the evidence of Placodermi affinities and accepts those of the Dipnoi. 
“Die Dipnoer .... sind den Arihodira niher verwandt .... mit 
den Placodermen nicht so nah wie friiher angenommen.” 
The revision of the Amphibia and Reptilia has been well done by 
‘Broili; one misses little that should be included in the work. The 
many new discoveries among extinct amphibia have been intercalated 
without change in the classification, notwithstanding the new schemes, 
especially those of Jaekel, which have been proposed—and which yet 
or 
